Preheat oven to 375°F (190°C). In a large oven-safe skillet, brown ground beef over medium-high heat, about 6-8 minutes. Add onion and bell pepper, cook 4 minutes. Stir in garlic 30 seconds. Drain fat.

Add taco seasoning, beans, corn, tomatoes with green chiles, and 1 cup cheddar. Simmer 2-3 minutes.

In a bowl, stir corn muffin mix, creamed corn, egg, and remaining 1 cup cheddar just until combined.

Transfer beef mixture to a 9x13-inch dish (or keep in skillet). Spread cornbread topping evenly over the filling. Bake 25-30 minutes until golden and a toothpick comes out clean.

Let rest 5 minutes. Garnish with cilantro if desired, then slice and serve warm.