The other great thing about this recipe is that it uses melted butter. Melted butter is so easy to work with! But, there are two things you need to know: First, while you can melt the butter in the microwave or on the stove-top, if you use the microwave, be sure to cover the container with a paper towel, as the butter may get overheated and pop. Second, melted butter needs to cool a bit before you add it to the egg and sugar mixture. (If the butter is too hot, it can cook the eggs!) So let the butter sit at room temp until it’s just barely warm.