Preheat the oven to 400 F. Line a 12 cup muffin pan with paper liners.
Whisk flour sugar baking powder baking soda and salt in a large bowl.
In a second bowl whisk melted butter eggs milk and vanilla until smooth. Stir in lemon zest if using.
Toss blueberries with 1 tablespoon flour.
Pour the wet mix into the dry mix. Stir gently just until no dry streaks remain. Fold in blueberries.
Divide batter among cups filling almost to the top. Sprinkle with the remaining sugar.
Bake for 18 to 22 minutes until domed and golden and a tester comes out with moist crumbs.
Cool in the pan for 5 minutes then move muffins to a rack to finish cooling.