Recipe adapted from Epicurious
1/2 stick (1/4 cup) unsalted butter
3/4 cup all-purpose flour
1 1/2 teaspoons baking powder
1/2 cup yellow cornmeal
1/2 cup plus 1 tablespoon sugar
1 tablespoon freshly grated lemon zest
1/2 cup whole milk
2 large egg yolks
1/2 cup blueberries
Preheat oven to 375°F and line six 1/3-cup muffin cups or 2 mini muffin pans with paper liners.
Melt butter and cool. Into a large bowl sift together flour and baking powder and whisk in cornmeal, 1/2 cup sugar, lemon zest, and a generous pinch salt. In a bowl whisk together melted butter, milk, and yolks and add to flour mixture with half of blueberries, gently stirring until just combined.
Fill the cups evenly with batter and press remaining blueberries into tops of muffins. Sprinkle tops of muffins evenly with remaining tablespoon sugar. Bake muffins in middle of oven until tops are golden and a tester comes out clean (about 15 minutes for 1/3-cup-size muffins and 10 minutes for mini muffins. Remove muffins from cups and cool on a rack. Muffins keep in an airtight container at room temperature 2 days.