Preheat your oven to 400°F (200°C) and grease an 8-inch square baking dish or a cast-iron skillet.
In a large mixing bowl, combine the cornmeal, flour, sugar, baking powder, and salt. Mix well to ensure all the dry ingredients are evenly distributed.
In a separate bowl, whisk together the buttermilk, melted butter, and eggs until smooth.
Pour the wet ingredients into the dry ingredients and stir until just combined. Be careful not to overmix; a few lumps are okay.
Pour the batter into the prepared baking dish or skillet and spread it evenly.
Bake for 20-25 minutes, or until the top is golden brown and a toothpick inserted into the center comes out clean.
Allow the cornbread to cool slightly in the pan before slicing it into squares and serving.
