Directions

1. Pour sweetened condensed milk into a large bowl, and mix in the vanilla extract.
2. Using a mixer, whip the heavy cream and protein powder together until the mixture holds stiff, billowy peaks, about 3 minutes.
3. In a separate bowl, gently mix a scoop of the whipped cream into the condensed milk. This "lightens" the condensed milk and makes it easier to fold into the rest of the whipped cream.
4. Gently fold the rest of the whipped cream into the condensed milk. At first, it will look very lumpy. As you continue to fold, the mixture will smooth out and become soft and silky. Stop when you see just a few small lumps here and there; overmixing will cause it to deflate.
5. Place the mixture into a freezer container. Smooth the top with a spatula, then press a piece of wax paper against the surface to prevent ice crystals from forming.
6. Freeze for at least six hours, or up to 2 weeks: The ice cream will become more firm the longer you let it freeze. For best texture and flavor, eat within two weeks.