I love these solid bubble bars! These are made without glycerine so they harden up nicely and you don’t have to wrap them up tightly.
Solid Bubble Bath Bars
200 g arrowroot powder (or corn starch)
200 g baking soda
100 g SLSa
200 g liquid surfactant (I used Super Mild Surfactant Blend™ from Ingredients To Die For)
colorant and 2% fragrance
Mix all of the ingredients together until a dough forms. Mold or form however you want. Depending on how thick/big they are they might take a week or so to totally harden. Even then the inside might still be a bit moist when you break them up.