Buttermilk Corn Bread

Place oil in an 8-in. ovenproof skillet; tilt to coat bottom and sides. Place in a 425 degrees F oven for 10 minutes. In a bowl, combine cornmeal, flour, baking powder, salt and baking soda. Beat egg and buttermilk; add to dry ingredients just until moistened. Pour into the hot skillet. Bake for 15 minutes or until golden brown and a toothpick comes out clean. ');