Preheat and prep:
Preheat your oven to 350°F (175°C). Line an 8×8-inch baking pan with parchment paper, leaving some overhang for easy removal.

Combine wet ingredients:
In a large bowl, mash the ripe bananas until smooth. Add the eggs, maple syrup, Greek yogurt, vanilla extract, and melted coconut oil. Whisk everything together until smooth and fully combined.

Incorporate dry ingredients:
Sift the cocoa powder into the wet mixture to avoid lumps. Add oat flour, baking soda, sea salt, and cinnamon if using. Stir gently with a spatula or wooden spoon until the batter is thick and fudgy.

Add mix-ins:
Fold in the dark chocolate chips or chopped dark chocolate. If desired, add chopped walnuts or pecans for extra texture.

Bake and cool:
Pour the batter into the prepared pan and spread evenly. Sprinkle a few extra chocolate chips or nuts on top. Bake for 20–25 minutes until a toothpick inserted in the center comes out with a few moist crumbs. Let cool in the pan for 20–30 minutes before lifting out with the parchment and slicing into 9 or 12 squares.

Serving Information:
Prep Time: 10 minutes
Bake Time: 20–25 minutes
Total Time: 35 minutes
Servings: 9–12 brownies