In a large bowl, add the pancake mix and just enough water to make the batter slightly stiffer than pancake batter. Gently fold in the egg whites.
Spray the bottom and top of the waffle iron with cooking spray and immediately pour half of the batter onto the iron, starting at the center and moving to the edges. Spread the batter to the edges and sprinkle on about half of the chopped cookies, then close the iron without pressing too hard. Cook until the top is golden and a peek beneath reveals a golden crust as well, about 7 minutes; remove to a wire rack to cool completely. Spray the iron again and repeat with the remaining batter and cookies. When cooled, separate the waffle sections into 4 pieces.
Make the sandwiches by scooping ice cream onto one waffle square, then pressing another waffle square on top. Cut the sandwiches in half and press each edge into the chopped peanuts. If the ice cream is too soft, freeze the sandwiches until set. Eat right away or wrap in plastic and store in the freezer.