Place grated soap in blender and pour in boiling water.
Pulse slowly until all pieces of soap are dissolved. Do not blend too fast, it foams up very quickly. SHORT PULSES.
Let foam settle and pulse again to ensure the soap is all dissolved & blended.
Repeat once or twice more.
Allow to cool a bit.
Pour into foaming soap containers.
Recipe Notes
I would make this in small batches as indicated in the recipe – don’t try and double it. If you need more, just repeat. Because it foams some when blending you want extra room in the top of the blender.