Hi, I used so far for making soap a 2L pyrex and a size-matching mold. The jar fitted well my large pan to create a double-boiler to heat the oils and also to mix the soap. I'm thinking of upgrading to maybe a 5 lb mold. I don't think my pyrex will be enough. What do you use when making more than 1.5-2 kg of soap at once? It should be something heat-resistant... or do you heat the oils in something and after that making soap in something else? Need some ideas. Thanks!