Swiss Meringue

During my degree at catering school, we learned that there are two ways to make Swiss meringue. One way is to heat the mixture using a blowtorch and the oven, but I find that sugar crystallizes and becomes hard and lumpy. I much prefer the method below, using a bain-marie and sugar thermometer. As long as you use an accurate probe thermometer, it is foolproof. You can use this recipe on top of Key lime meringue pie.