01 - Preheat oven to 350°F. Line a 12-cup muffin tin with paper liners or grease lightly.
02 - In a medium bowl, whisk together flour, protein powder, baking powder, baking soda, and salt until well blended.
03 - In a large bowl, whisk Greek yogurt, eggs, milk, oil, sugar, and vanilla extract until smooth and creamy.
04 - Add dry ingredients to wet mixture. Stir gently until just combined—batter should remain slightly lumpy. Avoid overmixing.
05 - Toss blueberries with 1 tablespoon flour in a small bowl. Gently fold coated berries into the batter.
06 - Divide batter evenly among prepared muffin cups, filling each about three-quarters full.
07 - Bake for 18 to 22 minutes until a toothpick inserted into the center comes out clean.
08 - Let muffins cool in the pan for 5 minutes, then transfer to a wire rack to cool completely.