It is a mystery

I currently use a large glass bowl on top of a smaller pot, so I get lots of hot from the pot but the glass takes forever to get anything up to temperature, so a double boiler would be better. Or I use my stand mixer bowl if I'm doing something like a meringue but it's so oddly shaped that it doesn't sit well in there and I have to make a little holder out of aluminum foil for it to rest on.