Blend the batter: Add oats, banana, eggs, milk, protein powder, baking powder, cinnamon, salt, and vanilla to a blender. Blend until smooth and slightly thick.
Let it rest 2–3 minutes to hydrate.
Prep the filling: Stir the Greek yogurt in a bowl until creamy. Gently fold in berries. If using frozen berries, pat them dry to reduce excess moisture.
Heat the pan: Warm a nonstick skillet or griddle over medium heat.
Add a light coat of oil or butter.
Pour the base: Spoon about 2 tablespoons of batter per pancake onto the pan. Spread slightly to form small circles, about 3–4 inches wide.
Add the filling: Place 1 tablespoon of the yogurt-berry mixture in the center of each pancake round.
Seal the pancake: Top with another tablespoon or two of batter, covering the filling completely. Smooth gently with the back of the spoon.
Cook until set: When bubbles form and the edges look set (about 2–3 minutes), flip carefully.
Cook another 1–2 minutes until golden and cooked through.
Serve warm: Top with extra berries, a drizzle of honey or maple syrup, and a spoonful of yogurt if you like.