Ingredients
1 cup all-purpose flour
3 tablespoons plus 1 teaspoon granulated sugar
1 1/2 teaspoons baking powder
1/2 teaspoon coarse salt
3/4 cup whole milk
1 large egg, room temperature
2 tablespoons unsalted butter, melted, plus 1 tablespoon for pan
1 cup blueberries (about 5 ounces)
Confectioners’ sugar, for serving
Maple syrup, for serving
Preparation
Preheat oven to 375 degrees with rack in upper third. Place a 10-inch cast-iron skillet (or other nonstick ovenproof pan) in oven. Whisk together flour, 3 tablespoons granulated sugar, baking powder, and salt in a bowl. Whisk together milk, egg, and melted butter in another bowl. Whisk milk mixture into flour mixture until just combined.
Remove skillet from oven and add remaining 1 tablespoon butter, swirling to coat. Pour in batter and smooth top with an offset spatula. Sprinkle evenly with blueberries and remaining 1 teaspoon granulated sugar.
Bake until golden brown and cooked through, about 25 minutes. Remove from oven; let cool 5 minutes before dusting with confectioners’ sugar and serving with syrup.