In medium bowl stir together flour, baking powder, baking soda and salt.
3
In large bowl beat butter until light and fluffy. Slowly add brown sugar and then beat additional 2 minutes. Beat in banana, eggs and vanilla, just until combined
4
Stir in flour mixture.
5
Stir in oats and chocolate chunks.
6
Drop by heaping teaspoonfuls onto ungreased baking sheet. (I like to line my baking sheet with parchment paper or silicone baking mats.)
7
Bake 8 to 10 minutes or until lightly browned. Cool for one minute before moving to wire rack to cool completely.