I made this one before.. its not a SET recipe but it depends on what protein you use. If you can get protein powder that is for baking/cooking that would be better but I used just 100% whey (chocolate).
2 cups oatmeal
4oz nuts (what ever you like---I used cashews and peanuts) OR 4TBS NPB
4 scoops of protein powder
12-16 pckts splenda
..... mix together with water or milk (water is better since it would be able to stay out of the fridge for more than 4hrs).
You have to mix it slowly & keep adding water b/c if you add too much it will be sticky. After it is 'firm", either roll into balls or push down onto a pan covered with wax paper. Refrigerate. Makes 4 servings with the amounts I use. You can double them or whatever.... sometimes I use dried fruit (cranberries) and strawberry protein powder. When I make the protein balls I freeze them and then eat them later.