Preheat Your Skillet. Preheat your oven to 400°F. Place the cast-iron skillet in the oven while it preheats. This ensures the skillet is hot enough to create a crispy crust.
Mix the Dry Ingredients. In a large mixing bowl, combine cornmeal, flour, baking powder, salt, and sugar. Whisk to distribute the ingredients evenly.
Combine the Wet Ingredients. In a separate bowl, whisk together buttermilk, eggs, and melted butter. Make sure the butter has cooled slightly to avoid cooking the eggs.
Combine Wet and Dry Ingredients. Pour the wet ingredients into the dry mixture and stir gently until just combined. Avoid overmixing; the batter should be slightly lumpy.
Prepare the Skillet. Carefully remove the preheated skillet from the oven and coat it with a thin layer of oil or butter to prevent sticking.
Add the Batter. Pour the batter into the hot skillet, spreading it evenly with a spatula. You should hear a satisfying sizzle as the batter hits the skillet.
Bake. Return the skillet to the oven and bake for 20-25 minutes, or until the top is golden brown and a toothpick inserted into the center comes out clean.
Cool and Serve. Allow the cornbread to cool in the skillet for 5 minutes before slicing. Serve warm with butter, honey, or your favorite topping.