Ingredients

Parchment paper
Nonfat cooking spray
3/4 cup white sugar
3/4 cup dark brown sugar
1/2 cup plus 2 tablespoons unsweetened dark cocoa powder
2 whole eggs
4 egg whites
1 1/4 cups prunes, pured in a blender or food processor with 1/2 cup warm water
1 1/4 teaspoons pure vanilla extract
1/2 teaspoon salt
1/2 teaspoon baking soda
1/2 cup white flour
1/2 cup whole-wheat flour