Start by preheating your oven to 400°F (200°C). In a large skillet over medium heat, add the chopped onion and sauté until softened. This should take about 3-4 minutes. Toss in the minced garlic and continue to cook until fragrant. Next, add the ground beef and cook until it’s no longer pink. Drain any excess fat from the skillet. Now sprinkle in the taco seasoning, adding the black beans and corn. Mix well and let it simmer for about 5 minutes. This step allows the flavors to meld beautifully. If you’re a cheese lover, stir in some shredded cheese at this point.

In a separate bowl, combine the dry ingredients: cornmeal, flour, baking powder, baking soda, and salt. In another bowl, whisk together the buttermilk, eggs, and melted butter. Slowly fold the wet ingredients into the dry ones until just combined. Don’t overmix; lumps are okay.

Spread your taco filling evenly in a greased 9x13-inch baking dish. Pour the cornbread batter over the taco mixture, spreading it out gently to cover. If you like, sprinkle some additional shredded cheese on top.

Put the casserole into your preheated oven and bake for 25-30 minutes, or until the cornbread topping is golden brown and a toothpick inserted in the center comes out clean. The aroma will fill your kitchen, drawing everyone in.

Once baked, remove it from the oven and let it cool for about 10 minutes. This cooling time helps it set up a bit, making slicing easier. Serve it warm, topped with your favorite garnishes like sour cream, salsa, or sliced jalapeños.