Coat bottom and sides of an 8-inch cast-iron skillet with vegetable oil; heat in oven 5 minutes.
Whisk together buttermilk, egg, cheese, and cornmeal.
Pour into hot skillet.
Bake 25 minutes.
Cheesy Cornbread Muffins
Omit vegetable oil. Prepare recipe as directed, spooning batter into a lightly greased 12-cup muffin pan, filling three-fourths full. Decrease bake time to 15 to 17 minutes or until tops are golden brown.