For the ice cream, place egg whites in a mixing bowl. Use a handheld electric mixer to beat them into stiff peaks. Fold in the whey. Add sweetener to taste. Freeze for at least 1 hour (longer if you have time.)
Meanwhile, make the peanut butter cups by blending all the ingredients together in a blender.
Divide the peanut butter mixture into round muffin tins, filling about ¾ full. Place filled muffin tin in freezer and let freeze for about an hour or until firm.
When ready to eat, scoop ice cream into a bowl and top with two peanut butter cups.
