This is not the case for modern detergents, but is held over from when soaps were all made from lye. The polymerized layers of oil that you have will stay mostly in tact with some dish detergent and a light scrub sponge. After washing and drying mine off with a towel, I apply some oil and heat it on the stove for a few minutes to maintain the seasoning.
But absolutely mortar and pestle should never ever get soap, particularly something like a molcajete made from volcanic rock. I just wipe mine really thoroughly with a clean, damp cloth.
FuglyDuck@lemmy.world 7 months ago
victoria (cast iron maker that’s a above lodge but below others,) recommends using a little dish soap.
even if the soaps do remove some seasoning, you should have enough on there, and cooking with enough oil that it regenerates. That’s the secret to cast iron’s longevity, in point of fact. Every time you cook with it, you add some more to the seasoning. (it also can develop some marvelous flavors if you’re intentional in how you cook with it.)