Preheat oven to 375F. Whisk together the flour, baking soda, corn starch, and salt in a medium bowl and set aside.

Cream butter, bananas, and sugars together until light and fluffy. Beat in vanilla extract and eggs until combined. Stir in the flour mixture just until combined. Stir in chocolate chips. Optional: Refrigerate dough for 30 minutes.

Line two cookie sheets with parchment paper or lightly spray with cooking spray. Use a cookie scoop to scoop out cookie dough onto prepared cookie sheets.

Bake cookies for 9-10 minutes or just until they start to turn light, golden brown on top. Let cookies cool completely on cookie sheets.