Preheat the oven to 400°F (200°C). Grease a 9x13 inch baking dish.
In a medium bowl, whisk together the cornmeal, buttermilk, eggs, baking powder, baking soda, and salt until smooth. Set aside.
In a large skillet over medium heat, cook the ground beef or turkey until browned. Drain excess fat. Add the chopped onion and diced bell peppers to the skillet and sauté until soft.
Stir in the black beans, corn, diced tomatoes, taco seasoning, and salsa into the skillet mixture. Cook for an additional 5 minutes to incorporate the flavors.
Pour half the cornbread batter into the bottom of the prepared baking dish. Spread the meat mixture evenly over this layer, then top with the remaining cornbread batter, smoothing it out with a spatula.
Sprinkle shredded cheddar cheese over the top of the casserole.
Bake in the preheated oven for 30-35 minutes or until the cornbread topping is golden brown and a toothpick comes out clean from the center.
Allow the casserole to cool for about 10 minutes before slicing.
Notes
Serve hot, garnished with fresh cilantro and a dollop of sour cream or guacamole on top for added flair.