In large bowl, combine flour, oats, baking powder, salt, and baking soda. Stir in chocolate chips. Make a well in center of bowl.
In another bowl, beat together yogurt, brown sugar, peanut butter, oil, egg, egg whites, and vanilla until smooth. Pour into well in bowl of dry ingredients and stir just until moistened and blended. Do not overmix.
Spoon batter into prepared muffin tin, filling cups three-quarters full. Bake in preheated oven for 15-20 minutes or until done.