01 - Preheat oven to 400°F. Line a 12-cup muffin tin with paper liners or grease cups thoroughly with cooking spray.
02 - In a large mixing bowl, whisk together flour, granulated sugar, baking powder, baking soda, and salt until well combined.
03 - In a separate medium bowl, whisk eggs, vegetable oil, yogurt, lemon zest, lemon juice, and vanilla extract until smooth and fully incorporated.
04 - Pour wet mixture into dry ingredients. Gently fold together with a spatula just until combined—some small lumps should remain. Take care not to overmix.
05 - Toss blueberries with 1 tablespoon flour in a small bowl. Gently fold coated berries into the batter until evenly distributed.
06 - Divide batter evenly among the 12 prepared muffin cups, filling each about three-quarters full. Sprinkle coarse sugar over tops if using.
07 - Bake at 400°F for 18 to 22 minutes, until muffins are golden brown and a wooden toothpick inserted into the center comes out clean.
08 - Let muffins rest in the tin for 5 minutes. Transfer to a wire cooling rack and allow to cool completely before serving.