Preheat your oven to 400°F. Grease a 9×13-inch baking pan generously with butter or nonstick cooking spray (or try the hot-pan trick from the tips for extra-crispy edges!)
In a large mixing bowl, combine the cornmeal and flour.
Add the sugar, baking powder, and salt to the cornmeal-flour mixture. Whisk the dry ingredients together until evenly combined.
Make a well in the center of the dry ingredients. Pour in the melted butter, buttermilk (or milk), and eggs.
Gently stir the mixture, starting from the center and working outward, just until everything is combined and no streaks of dry flour remain (a few small lumps are perfectly fine—don’t overmix!).
Pour the batter into your prepared 9×13-inch pan (if you preheated the empty pan for extra-crispy edges, be careful—it’ll sizzle!).
Bake in the preheated 400°F oven for 20–25 minutes, or until the top is golden and a toothpick inserted in the center comes out clean.
Bake for 20–25 minutes, until the top is golden brown, the edges have pulled slightly away from the sides of the pan, and a toothpick inserted in the center comes out clean (or with just a few moist crumbs).
Remove from the oven, let cool for a few minutes, then cut into 15 squares. Serve warm with plenty of butter, honey, or alongside your favorite soup, chili, or beans!