Place all the ingredients in the bowl of a stand mixer, or a large heat-safe bowl to use with a hand mixer, and whisk together to combine well.
Place the bowl over a simmering pot of water, making sure the water doesn’t touch the mixing bowl, and cook until the mixture reaches 160°F on an instant-read thermometer, about 4 minutes. Remove from the heat and beat with the whisk attachment (or a hand mixer) on medium-high speed until light and fluffy, about 7 minutes.