Chocolate Chip Muffins

1 3/4 cups all purpose flour
1/2 cup whole wheat flour
2 1/2 tsp baking powder
1 ripe banana, mashed (approximately 1/2 cup)
1/2 cup brown sugar, packed
2 eggs
1 cup milk
1/3 cup butter, melted
1 cup chocolate chips

Preheat oven to 400 degrees F.  Butter 12 large muffin pans well
or line with paper muffin cups. Sift together flours, and baking
powder.  Reserve. Combine banana with brown sugar until smooth.
Beat in eggs, milk and melted butter.  Stir in dry ingredients only
until blended. Quickly stir in chocolate chips.  Do not overbeat.
Spoon mixture into prepared muffin cups.  (An ice cream scoop works
well for this). Bake 25 minutes or until browned slightly.  Cool
on racks.