Preheat oven to 350 degrees.
Mix Banana and Peanut Butter: Peel one medium to large banana and mash in mixing bowl. Add 3 tblsps peanut butter and mix well with banana.
Mix: Mix together oats, baking powder, and nuts.
With Banana and Peanut Butter in mixing bowl add mixture of oats, baking powder, and nuts. Mix together thoroughly. Drop rounded tablespoons of dough onto lightly greased baking sheets. Flatten slightly with moistened fingers.
Bake at 350 degrees for 15 minutes.