Using a digital scale, measure out your water and pour it into a heat-resistant glass or metal.
Measure out the lye and add it to the water. Stir the lye into the water slowly and stir until it dissolves. Note, the chemical reaction will cause it to heat up quickly.
Using the digital scale, measure out the cocoa butter, coconut oil, and shea butter. Pour into a saucepan and melt over medium heat.
Once the ingredients are melted, allow them to cool back down to 100 degrees.
Once the fats reach 100 degrees, it is time to mix the lye water with the oils. Slowly add the lye and water to the oils, mix with an immersion blender. This will take a couple of minutes. You will know it is the right consistency when the soap from the blender drips and pools up at the top of the soap in the saucepan. This is known as the trace.
If using essential oils, add those in now. Stir well.
Pour the soap into the soap molds. If using silicone soap molds, you don’t have to do anything to them before pouring them in. Other molds may require parchment paper.
Allow the soap to harden and sit in the molds for at least 24 hours or up to 3 days.
Remove the soap from the molds and allow it to cure for 3-4 weeks before using.