Prep the pan and oven: Heat your oven to 350°F (175°C). Line a 9x5-inch loaf pan with parchment and lightly grease the sides.
Mash the bananas: In a large bowl, mash bananas with a fork until mostly smooth with some small lumps.
Add the wet ingredients: Whisk in eggs, Greek yogurt, maple syrup or honey, vanilla, and oil until well combined.
Mix the dry ingredients: In the same bowl, add oat flour, protein powder, baking powder, baking soda, cinnamon, and salt.
Stir gently until just combined. Don’t overmix.
Fold in extras: If using nuts, chocolate chips, or seeds, fold them in now.
Fill the pan: Pour the batter into the prepared loaf pan and smooth the top.
Bake: Bake for 40–50 minutes, or until a toothpick comes out clean or with a few moist crumbs. If the top is browning too fast, tent loosely with foil for the last 10 minutes.
Cool properly: Let the bread cool in the pan for 10 minutes, then lift it out and cool on a rack for at least 30 minutes before slicing.
This helps it set and stay moist.
Slice and serve: Cut into thick slices and enjoy warm or at room temp. Add a smear of peanut butter or yogurt for extra protein.