The most important thing in preparing protein cream at home is to properly separate the whites from the yolks. They should be clean, without a single drop of yolk. Otherwise, the egg cream simply won’t work. The easiest way to do this is to simply crack an egg over a container and pour the yolk from one shell to another. This way the protein will flow into the container on its own. Protein cream is ideal for filling puff pastries or shortbread baskets.