Posted by: soapchix | February 25, 2008

How to make cold processed (castile) soap in 13 steps; a tutorial

With so many articles being written about how many chemicals there are in soap and bath products, we have had lots of requests to share our soapmaking recipe so you can do it at home. If you can bake a cake, you can make soap, so here’s our tutorial for a basic bar of lavender soap.
By the way, did you know that because most commercial ‘soaps’ are actually ‘detergent bars’, they can’t put the word soap on the label. True Story! Dove calls themselves ‘Beauty Bars’, Oil of Olay has Body Wash‘, Palmolive has ‘softsoap’, which is almost soap but not quite.

Anywho, back to the tutorial.

1) find a great apron. It will help summon the wisdom of your great grandma, who could tell you a thing or two about making soap.

2) get some dark chocolate and peanut butter. There will be some free time when you are waiting for the temperatures to get to the right point…chocolate & peanut butter is just the thing to pass the time. Trust us!


3) get some soap molds ready to pour soap into. We have collapsible wooden molds, you can use a cardboard box with the sides cut down to size. The most important thing is to remember to line them with freezer paper (shiny side down), saran wrap, or butcher paper.

wooden soap molds

4) get a recipe. Ashley and I guard our secret soap formula like Coke guards their syrup formula. Except if you babysit my kids and I come back from a date with Hubby drunk off of Coldstone ice cream. Then, I’ll tell you anything. But, until then, check out all these recipes that other people have shared. A good, beginner one to start with is this olive oil soap recipe:

40oz olive oil
10 oz water
5 oz lye
1 oz fragrance

This will make a shoebox size loaf of soap that can be cut into 10-15 bars, depending on how thickly you slice it. We slice our bars into 6 ounces, which is a generous size, and we get 10 bars out of this.

5) Put on safety gear…safety glasses and rubber gloves. Seriously people! Because you are about to handle lye, aka drain cleaner. It’s nasty stuff. Remember the ‘chemical burn’ scene in Fight Club? That will happen to you without protective gear. True Story! Once you are protected, get out the lye (found at any Hardware store, and sometimes the cleaning section of your grocery store) and add it to the water. Stand back when you do this (or, as far as your arm will let you) and don’t breathe in deeply…the fumes are nasty. Always add lye to water, not the other way around.

water and lye in CP soap

6) Then measure out the oil in one pan (anything except aluminium!) and the essential oil in the other. It’s important to get the measurements right, so use a digital kitchen scale if possible. Even the littlest mistake makes a big difference in soap making!

7) Now, you wait for the lye/water to get to 110-115 degrees (oh, you’ll also need a digital thermometer. Temperature also makes a big difference, or you’ll make a soap volcano. Happened to The Soapchix a few times. True Story!) This is when you break out the chocolate.

8) Once the temperature is right with the lye/water, heat the oil up to 110-115, then remove from heat and add the lye/water to them. This is when it gets fun! Make sure you have no distractions from this point on, or you’ll end up with a bunch of goopy glop. This is why Ashley and I do most of our soapmaking after the kids go to bed. That, and the dangerously toxic lye.

adding lye/water to oils in CP soap

9) Once you add the lye/water into the oil, then it’s time to mix with a stick blender. What, I didn’t tell you that you needed a stick blender? Well, you do. Or you’ll be mixing it by hand for hours and hours. Actually, that might depend on the size of your batch of soap. We make bigger batches, but maybe if it’s a smaller batch you can get away with mixing it by hand. Although, it’s worth it to get a stick blender, just because they’re fun to have around.

mixing lye/water with oil in CP soap

10) You want to mix this mixture until it gets to ‘trace’, which means it’s thickened up and looks a bit like pudding when it starts to thicken:

trace in CP soap

11) This is the time to add in all the fun stuff! For our simple recipe, we’ll leave it at essential oils for you. When we do our soaps, we use the opportunity to add ground oats, lavender buds, honey, extra oils & butters, loofah, and things like that. Again, this is top secret, so I can’t tell you everything we do, unless you take my kids to the park and I get a 2 hour nap…then I’ll tell you anything you want to know.

I seem to have misplaced my lavender pictures, so here’s our lavender mint being mixed. First the color (no dyes! just ultramarines and minerals!):

adding color in CP soap

Then blend and mix:

Then comes the essential oils; mix and blend:

12) When it gets nice and thick (but not too thick!) and nice and blended, pour it into your mold like this:

See how dark and liquidy it looks? This means it has entered the ‘gel stage’…it’s when the magic happens. They lye is heating up the oils, causing saponification. You want to help this along by covering the top of your mold with a blanket and tucking the sides down around it. Also, sing a little song to the soap while doing this…it makes it happy and extra lathery. True Story!

13) Leave it alone for a day or two, until it looks lighter and feels more solid:

Then, unmold it and cut to your own liking. But don’t use it yet! It’s still a little soft. Find a nice, happy place to leave it for a few weeks (!!! I know! Weeks!!!) to make it a nice, hard bar of soap. Treat it like a plant during this time, and make sure to talk to it a few times a day. Say things like, “Who’s the cutest bar of soap ever? You are! And who smells so good? You do!” Soap really likes it when you encourage it like this.

Ashley even donated her dining room space to make sure she could keep an eye on them:

<img src=”Photobucket” alt=”lots of handmade soap!” />

And there you go! Handmade, cold processed, phthalate free, paraben free, laryl sulfate free, all natural, and totally super bar soap!

If you have any questions, comments, or grammar corrections, you can email us at soapchix (at) gmail (dot) com. And, if you’d rather not make soap in 13 steps, but still want some, take a gander at our soaps at

To recap:

Recipe (being a true castile soap, this will be less lathering, but don’t let that fool you! We’ve been brainwashed by all the lauryl sulfates out there into thinking that lather = better cleaning. It’s not true, especially in the case of this soap. It’s a lovely, if less lathering, bar.):

40oz olive oil
10 oz water
5 oz lye
1 oz fragrance

Equipment you’ll need:

soap mold, lined.
digital thermometer
digital weight scale
stick blender
non aluminum pots to mix soap in


Olive oil
essential oil
chocolate & peanut butter

About these ads


  1. I’ve been thinking about adding soaps to my product line for some time now. You make it look so easy! I may have to try it….


  2. Tiffany and Ashley, will you explain to me why the lye doesn’t harm the skin once it’s in soap form? It seems so counterintuitive, but I know it’s been done this way for hundreds and hundreds of years. What gives?

  3. yes i am also interested in this question. Please give an answer. is this soap then ecological, or still not?

  4. I just made my first batch of soap and it is sleeping nicely wrapped in its little blanket. We’ll see what it looks like tomorrow but it seems like every thing went well! Thanks for the tutorial!

  5. I’m wondering just HOW stinky is that lye? I ask because I have two dogs and a cat and a small house.. I dont’ want to offend anyone’s noses or make eyes water…


  6. What is the estimated poundage for the recipe you listed? I’m investing in some wooden soap molds and would like to get molds that can hold both full and halved recipes.

    Thanks for a great tutorial!

  7. Please help me
    Can I usecoconut fat as a replacement for coconut oil for soap making. How much fat should put.

    Example: 1oz coconut oil =?oz coconut fat

  8. [...] baby What’s the difference between Phthalates and Parabens? Feeling ambitious? Make your own! Soapchix Soap Making Tutorial (wish my best friend Holly lived closer to tackle this [...]

  9. I think this is a great recipe, really easy (I’m a first-time soapmaker), and my darling little soaps have been cut and I can’t wait till I can finally use them!

    I’m going to try to answer some of the questions above, based on what I’ve read:

    1. Lye in the soap. Once it’s a soap, there is no longer any lye, just soap. The lye is used to start a chemical reaction in the oil to make it soap. So at the end of the process, the lye is used up.

    2. Stinky lye. It’s not too bad. I have a dog and 18mo old daughter, and I just did the mixing outside the house and it was fine. Just had to turn back/away occasionally.

    3. This recipe made me about 13 bars of 100gram soaps. So 1.3kg is about 2.86lbs.

    4. I have no idea re coconut fat as this is my first time to make soap at all. I do know there’s some debate about coconut oil in soaps…it can be very drying. Some people don’t notice it, but I do when I use soaps that use coconut oils as base, but that maybe because I have dry skin. :(

    Hope this helps.

  10. love this howto =)

  11. for the question about why doesnt the lye effect the skni. Well once lye and oil/fat are mixed together, they both ‘died’ and cured (meaning: all the harmful reaction is taken out form each other). Some thing like: it cancel each other. The lye cancel the oil/fat to form residue to our skin, and the oil/fat cancelled the lye to cause a caustic effect to our skin. Its a fundemental chemistry.

  12. nd the oil/fat cancelled the lye to cause a caustic effect to our skin. Its a fundemental chemistry.

  13. [...] Serendipity Soap Dish : Un savon de Castille en 13 étapes…et avec humour ! (Que les non-anglophones ne cherchent pas quoi faire avec le chocolat et le beurre d'arachide, c'est pour manger en attendant que la soude refroidisse… ) [...]

  14. [...] you want pictures of the process have a look at SoapChix’s 13 Steps to Cold-Processed Castile Soap. They use a slightly different recipe that makes a bit less soap at a go but step No. 2 in their [...]

  15. The fact that the soap is not harsh to the skin is not at all counter intuitive when you think in terms of the chemistry going on. NaOH (lye) is a very strong base (hence its caustic nature) and attacks triglycerides (fats) in the oil, turning them into glycerol and soap. You can think of it in terms of the OH part of NaOH going to the glycerol, and the Na going into the soap. Although Na+ ions are unreactive, they give soap the ability to wash away grease from your skin. And since the harmful OH- part of lye is bonded tightly in glycerol it wont be able to harm your skin. Hope that explains it in simple terms.

  16. If anyone wants to see an excellent, clear and simple explanation of the chemistry of soap-making, Google “wolves and bunnies” to find a free educational site about the process in cartoon form. It explains how the lye (wolf) eats peaceful sheep (oils) and turn into useful sheepdogs (soap) and soft fluffy bunnies (superfatting oils).

  17. Hi, I was wondering if you could give me the measurements of your wooden soap molds? I would like to make some for doing my soap with. I like the way they have the wing nuts on the ends so you can get the soap out.
    Thank you for these very good directions!!!

  18. hey instead of putting artifficial fragrance in it is it possible to use lavander or petals???????????

  19. hey is it possible to add organic fragrance like lavender ir petals??????????????????????????

  20. Sa-Weet! :scampers off to find lye:

  21. Great post. I just stumbled on your blog. I am always amazed to read the different processes people use when making soap. I look forward to reading more.

  22. I wanted to ask how much it costs to make a batch?

  23. Hi,

    I’ve read that you must do a p.h test on your soap after it’s been cured, some say you need a P.H paper or just to use your tongue. Please tell me what you do with your soap. And do you need a stick blender or is it possible in small batches to mix by hand? The equipment used in this recipe, the pots, jugs, etc, would you give them a good wash and use them for food?


  24. I just made soap using your method….I have a silly question. The stick blender that I used, can I only use it for soap or can I still use it when i cook????
    Also…right after I poured into molds, I wrapped it in wax paper. I think I should not have done this because it looked like the blob pouring over the sides. I think I was able to save it though.

  25. [...] How to make cold processed (castile) soap in 13 steps; a tutorial … Feb 25, 2008 … Recipe (being a true castile soap, this will be less lathering, but don't let that fool you! … [...]

  26. with your recipe, does this make ONE of your molds? (so you had to make 3 batches of this recipe to fill your 3 molds?)
    also what are the dimensions of your molds that you used?
    i want to attempt this recipe tonight but want to make sure that i have everything ready! thank you so much!

  27. Thank you for the easy to follow steps. I am also thinking about adding soap to my products. Great blog site!

  28. Thanks for this posting! I was looking for a soap recipe that only had olive oil and lye!


  29. hi if lye is toxic wont it hurt my body an ingredient in the soap. ???

  30. I want to know if this process can be done using a castile liquid base like Dr Bronners? Like can I just heat that up and add what I want to it? or mix stuff with it and put it in the freezer?

  31. This is a great recipe. But if you add caster oil to
    the mix just before trace you get a real good lather. True story!

  32. how easy is it to clean the stick blender for food processing afterwards?

  33. If you want more lather in your castille soap, add a little coconut oil. Gives it some bubbly lather, I’ve heard. :)

    Is there an option other than lye?

  34. I’ve heard if you want more of a lather in your castille soap, add some coconut oil. It won’t be “pure” castille soap, but it gives it a nice bubbly lather. :)

  35. I found your blog and I can tell how much love you put on your craft, thanks for the posting i learned a good bit, do you still need a nanny? :)

  36. Soap is absolutely fine for your skin, even with the caustic lye. The reason why is similar to why table salt is fine to eat. It’s even required for our bodies. Salt is made of sodium, which reacts violently with water and chlorine, which in it’s gaseous form is a toxic gas. But, when they combine together, the chemical reaction that occurs gives us a totally different substance with totally different properties. Just like salt, when the lye reacts with the fats, saponification occurs, which is a chemical reaction. The resulting soap has completely different properties than the lye. It’s no longer dangerous. So, go ahead, use lye in your soap, just be careful until the chemical reaction has completed. Also, you want to make sure to use a good recipe. If you don’t have enough oils, lye that doesn’t have oil to react with will stay on your soap and that won’t feel good at all to wash with. You can carve it off, but better yet, go for a superfatted recipe, one that has a bit more oil than is actually need for all of the lye to react. It’ll help ensure this doesn’t happen.

    Going all natural does not mean going chemical free. There’s no escaping using chemicals, everything that is matter is made out of chemicals. Making your own soap ensures that no harmful chemicals are used, such as preservatives and stabilizers.

  37. Hello every one I have question about the water use in making soap.I live in New york city if I use tap water will it change the quality of my soap or should I use bottle water or should I boil the water first.I want to make the best soap possible.

  38. That was great. You should do a video. I get asked these questions all the time and a basic recipe is great. Folks don’t understand that detergents dry your skin and our soaps are nourishing. Dee

  39. I have a bookcalled The Complete , and it says just the opposite about the lye and water? Wondering where you got your info?
    And who’s right???

  40. Great advice – I’ve always wanted to try this and we have a plentiful supply of olive oil so maybe I’ll give it a go!

  41. Acid into Water when making soap, easy way to remember is lye is a caustic acid, L for Lye, CA for Caustic Acid always come first in the alphabet before W for Water.

  42. Holy crow. PLEASE don’t try to make soap from this recipe if it’s your first time. These instructions are terrible unless you already know what you’re doing!
    You don’t mention whether to measure in fl oz or lbs and oz. My digital scale measures in both. It’s by WEIGHT PEOPLE!!! And you don’t even explain that you need to gently stir the lye/water mixture until the lye dissolves.
    I tried making this by following the instructions here and ended up wasting 5 fl oz’s of lye by measuring wrong and then not stirring which caused it to solidify in the bottom of my pyrex measuring jug, which I then had to throw away because I couldn’t get the lye out of the bottom without using an icepick or something.
    PLEASE find another tutorial if you’re making soap for the first time, like I was. This one is the poops.

  43. What’s up colleagues, how is all, and what you would like to say about this article, in my view its really amazing for me.

  44. amazing and easy (I hope) My soap is wrapped up in towels now I will check in the morning. My only advise is NEVER use the blender/dishes etc for food always keep them separate. Thanks for a great tutorial!!

  45. I visit each day some web pages and information sites
    to read articles, but this blog gives feature based writing.

  46. I’ve made soap, but I’ve obviously missed some of the nuances such as chocolate, singing and praising my soap. You are my kind of soap makers!

  47. Hey guys I have just made some soap … what a fun experience ;) However instead of pouring the “thickened liquid” into a wooden or plastic mold I did place it into a glass container. After a minute or 2 I could so some sort of “sponge eruption” or similar. I immediately poured the content into a plastic bowl instead, stirred it again to sort of make it homogeneous again. Since I moved the content in a plastic container no more reaction occurred. Do you think the reaction was caused by the contact with glass? And above all … do you think I can still use this soap? If it wasn’t the glass, could it have been the fact that I mixed 3 fragrances? Or that I added 100 ml of Avocado oil just before the fragrances?

  48. Forgot to mention …. THANK YOU IN ADVANCE ;)

  49. It can’t possibly be emphasized adequately, that you should receive a photographs genital warts solution when you first can possibly when your sexual health
    is in risk right. Really wart is taken off, it
    doesnt grow back in the same position. Interestingly, your vehicle resolve
    someone episode, you are able to additional episode future,
    extremely have a closer ocular when you strike it to start out
    your family photos hpv warts medicine beginning of the, that helps solve
    any Warts signs substantially unlike should you allowed them to dispersed as well as the bloom for a.
    Select a process once you possibly can.Warts trying out for female

  50. […] Here is a really good recipe for making soap, it’s the one I used last year (my failure in last years batch was due more to not mixing it well enough to reach trace, than a problem with the recipe, I think).  I didn’t add anything fancy at trace, like they do, it was just pure soap. […]

  51. Hmm it looks like your site ate my first comment (it
    was extremely long) so I guess I’ll just sum it up what I wrote and say, I’m thoroughly enjoying your blog.

    I as well am an aspiring blog blogger but I’m still new to the
    whole thing. Do you have any points for novice blog writers?

    I’d certainly appreciate it.

  52. This design is incredible! You certainly know how to keep a reader amused.

    Between your wit and your videos, I was almost moved to start my
    own blog (well, almost…HaHa!) Fantastic job.
    I really loved what you had to say, and more than that,
    how you presented it. Too cool!

  53. Good day! This is my first visit to your blog!

    We are a group of volunteers and starting a new initiative in a community in the same niche.

    Your blog provided us useful information to work on. You have done a marvellous job!

  54. Hi there, just became alert to your blog through Google, and found that it is truly informative.
    I am gonna watch out for brussels. I will appreciate if you
    continue this in future. A lot of people will be benefited from your writing.

  55. Hey! I know this is kinda off topic but I was wondering which blog platform are you using for this website?

    I’m getting sick and tired of WordPress because I’ve
    had issues with hackers and I’m looking at options for another platform.
    I would be fantastic iif you could poiunt me in the direction of a good platform.

  56. This is really interesting, You’re a very
    skilled blogger. I have joined your feed and look forward to seeking more of
    your great post. Also, I’ve shared your web site in my social networks!

  57. Thank you for the auspicious writeup. It actually used to
    be a enjoyment account it. Look advanced to more introduced agreeable from you!
    However, how can we keep up a correspondence?

  58. […] How to make cold processed (castile) soap in 13 steps; a […]

  59. […] How to make cold processed (castile) soap in 13 steps; a […]

  60. […] How to make cold processed (castile) soap in 13 steps; a … – Feb 25, 2008 · Posted by: soapchix | February 25, 2008 How to make cold processed (castile) soap in 13 steps; a tutorial… […]

  61. […] How to make cold processed (castile) soap in 13 steps; a … – Feb 25, 2008 · 2 wild friends, 1 soapy dream. Taking over the world, one bar of soap at a time… […]

  62. […] How to make cold processed (castile) soap in 13 steps; a … – Feb 25, 2008 · Posted by: soapchix | February 25, 2008 How to make cold processed (castile) soap in 13 steps; a tutorial… […]

  63. […] How to make cold processed (castile) soap in 13 steps; a … – Feb 25, 2008 · Posted by: soapchix | February 25, 2008 How to make cold processed (castile) soap in 13 steps; a tutorial… […]

  64. […] How to make cold processed (castile) soap in 13 steps; a … – Feb 25, 2008 · 2 wild friends, 1 soapy dream. Taking over the world, one bar of soap at a time… […]

  65. […] How to make cold processed (castile) soap in 13 steps; a … – Feb 25, 2008 · Posted by: soapchix | February 25, 2008 How to make cold processed (castile) soap in 13 steps; a tutorial… […]

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s



Get every new post delivered to your Inbox.

Join 28 other followers

%d bloggers like this: