Heat oil in an 8-inch cast-iron skillet or muffin pans in a 450° oven 5 minutes.
Combine cornmeal and next 4 ingredients in a medium bowl; make a well in center of mixture.
Stir together buttermilk and egg; add to dry ingredients, stirring just until moistened. Pour into hot skillet.
Bake at 450° for 20 minutes or until golden.