Preheat oven to 375 degrees F.
Mix all dry ingredients together until well combined. In a separate bowl, whisk together wet ingredients. Add liquid to dry ingredients and stir well.
Lightly oil a 10- or 12-inch inch cast iron skillet. Pour batter into skillet and spread evenly
Bake for about 30 minutes, until golden. A 10-inch skillet will take a little longer than a 12-inch. The top of the cornbread should be firm to the touch (if cracks develop, that is fine!)
Remove from oven and let cool 10 minutes before cutting into wedges.