Preheat oven to 400 degrees F. Prepare muffin pan with paper liners. Coat each with cooking spray.
In a large bowl, mix together the flour, baking powder,
walnuts, brown sugar, cinnamon, nutmeg and salt. Stir in
bananas, milk, butter and egg. Mix just until blended. Fold
in the chopped walnuts.
Fill muffin cups evenly with batter. Sprinkle with sugar and cinnamon.
Bake 20-22 minutes, until a toothpick inserted in the center comes out clean. Cool 1 minute and remove to wire rack.