How to fake a double boiler
There are a couple of ways to make a makeshift double boiler.
Pot-on-pot
You can stack two pots together. The lower pot will hold the boiling water, and the upper pot will hold the frosting ingredients.
If you stack the pots, it’s important that you don’t use a pot with a nonstick coating that will come off while you’re mixing the frosting.
Bowl-on-pot
You can also use a heat-safe metal or glass bowl placed over a pot of boiling water (pictured in the step-by-step how-to section above). I think this method is a little easier because it gives you more room to mix the frosting while it cooks.
>>Top tip: It’s important that you don’t let the bottom of the bowl or pot touch the boiling water.