Preheat oven to 175 degrees Celsius (350 degrees Fahrenheit) and grease a 9x5 inch loaf pan or line it with parchment paper.

In a large mixing bowl, whisk together the mashed bananas, Greek yogurt, eggs, and vanilla extract until the mixture is homogeneous.

In a separate bowl, combine the chocolate whey protein, oat flour, cocoa powder, baking soda, and salt, ensuring there are no large clumps.

Gently fold the dry ingredients into the wet banana mixture using a spatula until just incorporated; do not overmix as this can result in a rubbery texture.

Fold in 30g of the chocolate chips, reserving the remaining 10g for the topping.

Transfer the batter into the prepared loaf pan and smooth the top with a spatula, then sprinkle the remaining chocolate chips over the surface.

Bake for 45 to 50 minutes, or until a toothpick inserted into the center of the loaf comes out clean.

Remove from the oven and allow the bread to cool in the pan for 15 minutes before transferring to a wire rack to cool completely.

Slice into 8 equal portions to ensure the targeted protein distribution of 20g per serving.