Begin by preheating your oven to 200°C (400°F) and place a rack in the center. Grease a 9-inch cast iron skillet or a 9-inch square baking dish lightly with butter, then place it in the oven to warm up.

(If using a cast iron skillet: melt the ½ cup of butter directly in the skillet over medium heat on the stovetop. Once melted, remove from heat and let it cool slightly before incorporating into the batter.)

In a spacious mixing bowl, combine the flour, cornmeal, sugar, baking powder (if using), baking soda, and salt by whisking them together thoroughly. Create a well in the center of the dry ingredients and pour in the buttermilk and eggs. Stir until well mixed, then fold in the slightly cooled melted butter, ensuring not to overmix the batter.

Using oven mitts, carefully remove the preheated skillet or baking dish from the oven. Pour the batter into the hot skillet or dish, allowing the mixture to spread evenly. The sizzle you hear is a good sign that the skillet is properly heated.

Bake for about 20-23 minutes, or until the cornbread begins to turn golden on top and a toothpick inserted into the center comes out clean. Once done, let the cornbread cool for approximately 10 minutes before slicing and serving. Enjoy the warm, buttery goodness of your homemade cornbread!