Makes 12 muffin size or 48 mini muffin pan doughnuts
DOUGHNUTS
2 3/4cups (13 3/4 ounces) all-purpose flour
1cup (7 ounces) sugar
1/4cup cornstarch
1tablespoon baking powder
1teaspoon salt
1/2teaspoon ground nutmeg
1cup buttermilk
8tablespoons unsalted butter, melted
2large eggs plus 1 large yolk
COATING
1cup sugar
2teaspoons ground cinnamon
8tablespoons unsalted butter, melted
1. FOR THE DOUGHNUTS: Adjust oven rack to middle position and heat oven to 400 degrees. Spray 12-cup muffin tin with vegetable oil spray. Whisk flour, sugar, cornstarch, baking powder, salt, and nutmeg together in bowl. Whisk buttermilk, melted butter, and eggs and yolk together in separate bowl. Add wet ingredients to dry ingredients and stir with rubber spatula until just combined.
2. Scoop batter into prepared tin. Bake until doughnuts are lightly browned and toothpick inserted in center comes out clean, 19 to 22 minutes. Let doughnuts cool in tin for 5 minutes.
3. FOR THE COATING: Whisk sugar and cinnamon together in bowl. Remove doughnuts from tin. Working with 1 doughnut at a time, brush all over with melted butter, then roll in cinnamon sugar, pressing lightly to adhere. Transfer to wire rack and let cool for 15 minutes. Serve.
KEY STEP: BRUSH WITH BUTTER
We brush the warm muffins liberally with melted butter before rolling them in the cinnamon sugar. The butter helps the coating stick and makes the muffins taste more fried. Use your hand to press the cinnamon sugar onto the doughnuts to coat them completely.