01 -
Set your oven to 350°F and spray a 9x13-inch baking dish with non-stick spray.
02 -
In a large skillet over medium heat, cook the ground beef and chopped onion until the beef is browned and the onions are soft. Drain any excess grease.
03 -
Add garlic powder, salt, pepper, and Italian seasoning (if using) to the beef mixture. Stir to combine.
04 -
In a large bowl, mix the cooked rice, beef mixture, cream of mushroom soup, sour cream, and 1 ½ cups of shredded cheddar cheese.
05 -
Spread the mixture evenly into the prepared baking dish. Sprinkle the remaining ½ cup of shredded cheddar cheese on top.
06 -
Bake uncovered for 25–30 minutes, or until the cheese is melted and bubbly.
07 -
Remove the casserole from the oven and let it sit for 5 minutes before serving for easy slicing.