1. Brown the Beef
In a large oven-safe skillet or Dutch oven, cook the ground beef and onion over medium-high heat until the beef is fully browned. Drain any excess fat. Stir in the garlic, chili powder, cumin, salt, and pepper, cooking about 1 minute until fragrant.
2. Cook the Rice
Add the uncooked rice, diced tomatoes with juice, tomato sauce, and beef broth. Bring to a simmer, then reduce heat to low. Cover and cook 18–20 minutes, stirring occasionally, until the rice is tender and the liquid is absorbed.
3. Stir in the Cheese
Remove from heat and mix in 1 cup of cheddar cheese until creamy and melted. Sprinkle the remaining ½ cup over the top.
4. Broil and Serve
For a golden, bubbly finish, broil 2–3 minutes until the cheese lightly browns. Let the casserole rest 5 minutes before serving to thicken and set.