Mix 2 1/2 cups just-add-water pancake mix with enough water to make a stiff pancake batter. Beat 2 egg whites to medium peaks and fold into the batter. Spread half of the batter in a hot square waffle iron coated with cooking spray. Sprinkle with 1 cup chopped peanut butter sandwich cookies and cook until golden. Spray the waffle iron with more cooking spray and repeat to make more waffles; let cool. Separate the waffles into 8 squares. Sandwich with softened chocolate ice cream. Halve the sandwiches; press the edges in chopped peanuts.