Preheat oven to 350°F (175°C) and grease a 12-cup muffin tin with non-stick spray.

In a large mixing bowl, combine the rolled oats, protein powder, baking powder, salt, and cinnamon.

In a separate medium bowl, whisk together the eggs, Greek yogurt, almond milk, maple syrup, and vanilla extract until well combined.

Add the wet ingredients to the dry ingredients and stir until the mixture is uniform.

Gently fold the fresh blueberries into the batter.

Distribute the batter evenly across the 12 muffin cups.

Bake for 20 to 25 minutes, or until the centers are set and the edges are lightly golden.

Remove from the oven and cool in the pan for 5 to 10 minutes before transferring to a wire rack.