Preheat your oven to 350°F (175°C). Lightly grease a small oven-safe ramekin or dish (about 10–12 ounces) or use a small loaf pan.
Blend or mix the base. For a cake-like texture, add oats, protein powder, banana, milk, egg, maple syrup, baking powder, vanilla, and salt to a blender.
Blend until smooth, 10–20 seconds. For a heartier texture, whisk by hand and keep the oats whole.
Stir in the chocolate chips. Fold in most of the chips, saving a few to sprinkle on top.
Pour and top.
Pour the batter into the prepared dish and add the remaining chocolate chips on the surface.
Bake for 18–24 minutes, until the top is set and a toothpick comes out mostly clean. If you like a gooier center, pull it at the earlier mark.
Cool for 3–5 minutes. Enjoy warm as is, or top with a drizzle of nut butter, a spoonful of yogurt, or fresh berries.