Preheat oven to 325 degrees F.

Cut parchment paper⁠ the size of your cookie sheet and place on countertop.

In blender, puree banana and blueberries.

In medium bowl, whisk together dry ingredients. Pour wet ingredients over dry and mix thoroughly.

Wrap dough in plastic wrap⁠ and let rest 5 minutes.

Turn out dough onto parchment paper and roll to 1/4” thickness. Stay within the confines of parchment paper. You’ll be transferring it to your cookie sheet.

Using a pizza cutter, cut narrow strips vertically or horizontally. If dough starts sticking, wipe off cutter.

Repeat same process in opposite direction, resulting in a patchwork grid.

Transfer parchment paper onto cookie sheet and bake 10 minutes.

Remove cookie sheet and break up grid using a spatula or oven-mitted hands. Spread the bits around evenly on the sheet and return to the oven for 10-15 more minutes.

Remove the cookie sheet once more and stir the bits around with a spatula. Bake 10 more minutes.

Remove from oven, slide parchment paper onto a wire rack and let treats cool completely.