Hot process soap is my favorite method of soap making. Add lemon fragrance for a fresh scent. It’s fast, simple & easy, and you can use the soap the very next day. Similar to cold process soap, hot process soap is also made with oils and lye – but instead of stick blending until it hits trace (a thick batter) and being poured into a mold, it is mixed and heated in the slow cooker, somewhere between 140 degrees F and 176 degrees F. The recipe I’ve included here is one of my most popular, BEST soaps. Benefits of bar soap Whether you are trying to live sustainably or live frugally, this bar dish soap will help you get there. A simple recipe for cold process bar dish soap that gets your dishes sparkling clean. Hot Process Soap. This post is a detailed picture tutorial with complete instructions so you can make your own handmade hot process soap with confidence. Store bought dish soap is shockingly expensive and always comes in big plastic containers.