Aunt Lilly’s Farm Soap

Reader Contribution by RenÉE Benoit
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I think it’s appropriate that my last soap project for this series is a re-make of the soap that started me off on my soap adventures 50 years ago. If you remember from the castile soap project I mentioned that when I was a young woman my mother introduced me to an old woman named Lilly who lived on a farm near Iowa Falls, Iowa. Lilly was straight out of the pages of The Foxfire Books edited by Eliot Wigginton. She was the real deal and she showed me how to make tallow soap on her wood stove.

The only thing I’m going to do differently this time is I am going to use rendered pig fat (lard) instead of rendered beef fat (tallow). I purposely chose lard because I decided that if I had any leftover after rendering it that I could use it for cooking. Yes, I rendered my own lard for this project. Store-bought lard is—in my opinion—odious stuff. The texture is grainy. I simply don’t like it. Who knows how those pigs were raised and with what chemicals they were fed? I was also able to source pig fat from an organic pig who lived a good life and who was humanely dispatched. If you can’t do this please do what you are comfortable with.

By the way, soap made from animal fat is particularly good for skin irritations like poison oak or ivy and has a nice creamy lather.

This is my best soap so far. Photo by Renee Benoit

Rendering Pig Fat into Lard

  • 3 lbs of pretty clean pig fat (That means: as much of the meat removed as you can)
  • Slow cooker

Chop the pig fat into 1” chunks or smaller. If you have a meat grinder you can run the fat through the grinder. It will melt all that much faster. Put the chopped or ground fat into a slow cooker on LOW. If you put it on high it could brown the fat which will make it have a strong scent. Let it slow cook for a long time. It might take 6 hours. When it’s all melted and there are little brown bits (cracklins) floating in it, scoop the cracklins out with a slotted spoon and then strain the melted fat through a sieve and then cheesecloth to get rid of all the cracklins and particles. Letting particles stay in the soap can make the soap go rancid. You can fry the cracklins until crisp and eat them if you wish. No carbos there! The melted fat will be a light golden color but when it solidifies it will be white and gorgeously smooth.

This will keep in the fridge, covered, until you’re ready to make Farm Soap.

Lilly’s Farm Soap


  • 248 g (8.75 oz) distilled water
  • 103 g (3.65 oz) sodium hydroxide (lye)
  • 794 g (28 oz) rendered pig fat also known as lard
  • 25 g (.88 oz) lavender essential oil (optional)
  • 8 g (.28 oz) tea tree essential oil (optional)


  • Long sleeve shirt
  • Face and/or eye protectors (a weed wacker mask is awesome because I can wear my glasses with it)
  • Rubber gloves (regular dishwashing gloves work fine)
  • Immersion blender (you can blend by hand and there’s more control over splashing but it takes longer)
  • Stainless steel pot (I use 3 qt with high sides and a pour spout)
  • Silicone molds enough to make 12-1”x2”x3” bars
  • Wax paper
  • Tea towel or cloth
  • 2 Measuring cups (plastic is fine)
  • Candy thermometer
  • Digital scale (important: I wouldn’t try making soap without it. In the old days of guess-and-gosh sometimes soap would have too much lye in it and was very hard on skin!)

Using the digital scale measure out your distilled water and pour it into your high sided stainless-steel pot. I use gram measurement because I think it is most accurate. By the way fudging on the ingredients can put you at risk for having not enough or too much lye in the soap. (By the way, if you have too much lye in your soap you can grate it and use it for laundry detergent.)

Put on your protective gear and, using the same digital scale, measure out your lye. I use a dedicated plastic measuring cup for the lye especially. It just makes it easier to keep the equipment separate from my cooking utensils.

Still wearing your protective gear, stir the lye into the water with a stainless-steel spoon or the end of the immersion blender. Be careful not to splash. Just stir quietly. You’ll notice that the lye kind of crystallizes. Just stir and it will break up and dissolve. Then it will heat up. Stick your candy thermometer to touch the liquid and set it aside. It will probably heat up to about 150 degrees. Set it aside some place safe while you get the oil ready.

If you stored your lard in the fridge you need to melt it again. A double boiler works well for this. Set it aside until the lye water cools down to 100-110 degrees. Then carefully pour the melted lard into the lye water. Start by stirring with the immersion blender without it being turned on—it won’t take long—then turn the blender on low and mix until the mixture comes to “trace”. You know, the texture looks like rippling thin pudding. When the lard is barely starting to come to trace this is when you add essential oils if you want. Continue blending until it’s fully at trace.

Now fill your molds and let them set for 24 hours.

Put all your soapy equipment in the sink. Don’t wash it now as the equipment is covered with mixture where the chemical transformation is not complete. It’s still “hot”. Wait for 24 hours because then the transformation will be complete. No more lye!

When the soap has set up sufficiently—maybe a couple hours—cover it with wax paper and a light towel so it won’t set up too fast and crack or get “ash” on the surface. If it looks like it’s cracking move it to a cooler place (not freezing) just cooler. Ash is not a disaster by the way. It doesn’t look great but the soap works fine all the same. Check it after 24 hours but if it’s not hardening and coming away from the edges you might have to leave it longer up to 2 – 3 days. Then you’ll be able to unmold the soap to cure on a cooling rack. Cure it for about 4 weeks to make it harder so it will last longer.

If you want to use tallow instead of lard, increase the amount of lye to 105 g (3.7 oz)

If you follow my instructions you’ll never buy soap at the store again! How cool is that?