Make It
Step 1
Spray muffin tin with nonstick cooking spray.
Step 2
Whisk flour, ½ cup sugar, cornstarch, baking powder, salt and nutmeg in large bowl until combined.
Step 3
Whisk together buttermilk, ½ cup melted butter and eggs in a medium bowl. Add buttermilk mixture to flour mixture. Mix well with a rubber spatula.
Step 4
Spoon 2 tablespoons of batter in each muffin cup. Top batter with about ½ teaspoon dulce de leche. Cover dulce de leche with 1 tablespoon of batter.
Step 5
Bake at 400° F for 18 to 22 minutes or until donuts are light brown. Cool in pan for 5 minutes.
Step 6
Combine remaining ¼ cup sugar and cinnamon in a shallow bowl. Remove donuts from pan. Brush 2 tablespoons melted butter on top of each donut. Roll in cinnamon-sugar. Place on wire rack to cool completely.