Prep your pan and oven. Heat oven to 350°F (175°C). Line an 8-inch square pan or 9x5-inch loaf pan with parchment and lightly grease the sides.

Mash the bananas. In a large bowl, mash the ripe bananas with a fork until mostly smooth. A few small lumps are fine.

Whisk in the wet ingredients. Add eggs, oil, milk, vanilla, and the maple syrup or honey (if using). Whisk until well combined and slightly frothy.

Combine the dry ingredients. In a separate bowl, mix oat flour, rolled oats, baking powder, baking soda, cinnamon, and salt. Stir until evenly distributed.

Bring it together. Add dry ingredients to the wet mixture. Stir gently with a spatula until just combined. Don’t overmix—stop when no dry streaks remain.

Fold in extras. If you’re using nuts, chocolate, or fruit, fold them in now. Keep add-ins to about 1/3 cup total for best texture.

Fill the pan. Pour batter into the prepared pan and smooth the top. If you like, sprinkle a few extra oats on top for a homey look.

Bake. For an 8-inch square pan, bake 25–32 minutes. For a loaf pan, bake 40–50 minutes. The cake is done when the center springs back lightly and a toothpick comes out with a few moist crumbs.

Cool before slicing. Let the cake cool in the pan for 10 minutes, then lift it out to a rack. Cool another 20–30 minutes before cutting so it sets nicely.

Serve. Enjoy plain, or top with a swipe of almond butter, a dollop of yogurt, or a drizzle of warm peanut butter.