“Help! I do not have a double boiler!”
Well OK THEN! LET’S MAKE ONE!
But wait, I want to be clear about Why we use a double boiler in the first place.
When heating something in a pot, the portion that comes in contact with the very hot bottom of the pot will heat up more quickly than the rest of the food. This isn’t a problem for most foods, but it is a big problem for some things, such as chocolate and delicate sauces, and in the case of making Swiss Buttercream, the egg whites that coagulate very easily. The solution is to use a double boiler
A double boiler consists of a bowl placed on top of a pan of simmering water. The bowl does not touch the water, but creates a seal with the bottom pan to trap the steam produced by the simmering water. Inside the top bowl, you can melt chocolate without worrying that it will stick to the pot and burn.
You can buy a double boiler, but it’s easy to make one at home. All you need to make a double boiler is a mixing bowl (preferably glass/pyrex or metal) and a saucepan that the bowl will fit on top of.
I do it all the time when I make my swiss buttercream recipe, I simply place the work bowl of my Kitchen Aid mixer directly on the pot of steaming water.
The two should fit tightly together; you don’t want a gap between the bowl and the saucepan, nor do you want a bowl that is gigantic and cumbersome on top of tiny saucepan.
To use the double boiler, add water to the pan and bring it to a simmer, then place the bowl on top and fill it with whatever you intend to cook or melt.