The soapmaking process is what is known as an exothermic process; the process of turning oils, water, and lye produces heat. Additives like honey, or milk can increase the temperature in the mold even more. Oatmeal Milk & Honey soap is a notorious heater and this time was no different. I expected that.
I purposely waited for subzero temperatures before making a batch of this soap, one that overheats for me almost every single time. This past weekend, our daytime temperatures were hovering around -12C so I decided it was the perfect time to make a batch. The intention was to leave the mold outside, in the subzero weather.