Preheat oven to 400°F. Line a 12-cup muffin tin with paper liners.
Whisk flour, sugar, baking powder, salt, and cinnamon in a large bowl. Stir in lemon zest.
In a separate bowl, whisk egg, milk, oil, and vanilla until smooth.
Pour wet ingredients into the dry. Stir gently just until a few dry streaks remain.
Fold in blueberries carefully to avoid bursting. Do not overmix the batter.
Divide batter evenly among liners. Sprinkle tops with turbinado sugar.
Bake 16–18 minutes, until golden and a toothpick comes out clean or with a few crumbs.
Cool in pan 5 minutes, then move muffins to a rack to finish cooling. Serve warm or at room temperature.