Step 1

Preheat oven to 400 degrees F (200 degrees C).

Step 2

Heat a cast-iron skillet over medium-high heat. Cook and stir beef in the hot skillet until browned and crumbly, 5 to 7 minutes; drain and discard grease. Season beef with salt and pepper.

Step 3

Stir onion into the ground beef; cook and stir for 1 minute and immediately remove skillet from heat.

Step 4

Stir pinto beans and crushed tomatoes into the beef mixture.

Step 5

Beat cream-style corn, cornbread mix, and egg together in a bowl until smooth; spread over the top of the ground beef mixture in the skillet. Sprinkle Cheddar cheese over the corn mixture.

Step 6

Bake in preheated oven until the cheese is melted and the cornbread is set in the middle, about 25 minutes.