Prepare the Chili:
In a large skillet, cook the ground beef or turkey over medium heat until browned.
Add the diced onion and minced garlic; sauté until softened.
Stir in the diced tomatoes, tomato sauce, kidney beans, and corn (if using).
Season with chili powder, cumin, smoked paprika, and cayenne pepper.
Simmer for 20 minutes, stirring occasionally.
Prepare the Cornbread Topping:
In a bowl, mix together cornmeal, flour, sugar, baking powder, and salt.
In another bowl, whisk together milk, vegetable oil, and egg.
Combine the wet and dry ingredients until just mixed.
Fold in shredded cheddar cheese if desired.
Assemble and Bake:
Preheat the oven to 375°F (190°C).
Transfer the chili mixture to a greased 9x13-inch baking dish.
Pour the cornbread batter evenly over the chili.
Bake for 25 minutes, or until the cornbread is golden brown and a toothpick inserted into the center comes out clean.
Let it cool for 5 minutes before serving.