Step 1

Preheat the oven to 375 degrees F (190 degrees C).

Step 2

Heat olive oil in a 10-inch cast iron skillet over medium heat; cook onion until soft, about 5 minutes. Stir in ground beef and cook until browned, about 5 minutes more. Drain grease.

Step 3

Add kidney beans, tomato sauce, corn, chili seasoning, salt, sugars, garlic powder, and Worcestershire sauce. Cook and stir until thoroughly heated, 5 to 10 minutes. Remove from heat and smooth out the top.

Step 4

Combine cornbread mix, milk, and egg together in a bowl. Mix until a slightly lumpy batter forms. Drop big spoonfuls of the cornbread mixture over the chili; smooth out to the edges of the skillet.

Step 5

Bake in the preheated oven until top starts to brown, about 15 minutes. Sprinkle Cheddar cheese on top and continue baking until cheese is melted, about 5 minutes more. Let casserole rest for 5 minutes before serving.