2 ounces bacon fat or other fat 2 cups cornmeal, preferably course ground 1 1/2 teaspoons kosher salt 1/2 teaspoon baking powder 1/2 teaspoon baking soda 1 1/2 cups buttermilk 1 large egg, beaten 4 tablespoons unsalted butter Preheat the oven to 450 degrees. Place the cast-iron skillets in the oven to preheat for at least 15 minutes. While pans are preheating, combine the cornmeal, salt, baking powder, baking soda in a medium bowl.