Preheat broiler.
Combine cookie crumbs and sugar in a small bowl.
Hollow center of peach halves using a melon baller. Arrange peaches, cut sides up, in an 8-inch square metal baking pan coated with cooking spray. Broil 2 minutes. Remove pan from oven. Carefully fill each peach half with 1 rounded tablespoon cookie crumb mixture. Place 1 teaspoon butter on top of each filled half. Broil 2 minutes or until butter melts. Sprinkle evenly with chocolate. Cool 5 minutes before serving.
