Disclosure:  This post contains affiliate links. If you click through and make a purchase, I may earn a small commission at no additional cost to you. I only recommend products I’ve personally used or believe will add value to your creative projects. There’s one ingredient that always sparks debate when people first learn about handmade soap : lye . It sounds scary — like something out of a high school chemistry lab. But here’s the secret soapmakers have known for centuries: