Preheat oven to 375 degrees F.
In a large bowl, combine flour, oats, baking powder, baking soda,
salt and brown sugar, set aside.
In a food processor (or blender/mixer) combine yogurt, bananas,
melted butter, peanut butter, milk, egg and vanilla until very well
blended. Mixture will be fairly thick.
Combine the wet with the dry ingredients, stir until combined but
do not over mix.
Mix in the chocolate chips.
Scoop batter into a greased muffin tin (regular size or mini).
Bake for 10-12 minutes for minis and 18-22 minutes for regular
sized or until a toothpick comes out clean.