Whisk the oat flour, protein powder, and baking powder in a microwave-safe bowl until well combined.
Add the egg whites, almond milk, and vanilla extract to the dry ingredients and stir until a smooth batter is formed.
Gently fold in half of the blueberries to distribute them evenly.
Microwave on high power for 90 to 120 seconds, or until the batter has risen and the center is firm to the touch.
Allow the bowl to rest for 60 seconds to complete the carry-over cooking process.
Garnish with the remaining blueberries and almond butter before serving.