Step 1

Preheat the oven to 350F (180C). Coat the interior (bottom and sides) of an 8-inch (20 cm) baking ban with nonstick cooking spray (see notes for alternative nonstick options).

Step 2

In a large mixing bowl, whisk the almond flour, oat flour, and baking soda until blended.

Step 3

Add the mashed bananas and nut butter to the bowl with the dry ingredients. Stir until completely combined. If you like, add chocolate chips to the batter. Stir until combined.

Step 4

Spread the batter into the prepared baking pan. Using a rubber spatula or the back of a spoon, spread the batter in an even layer, smoothing the top.

Step 5

Bake the bars in the preheated oven for 25 to 30 minutes until set at the center and golden brown at the edges. (Note: ovens and environments vary, so check at the earliest time and bake longer--even beyond the the max time--as needed).Transfer the pan to a cooling rack and cool completely.

Step 6

Transfer the pan to the refrigerator and chill for one hour (or place in the freezer for 15 minutes). Chilling the bars will make them easier to remove from the baking dish.

Step 7

Once chilled, cut into 16 bars or squares.