Preheat your oven to 375°F (190°C). In a large skillet, cook the ground beef along with the diced onion and minced garlic until the beef is nicely browned and the onions are soft. Drain off any excess fat - this keeps your casserole from getting greasy.
In a greased 9x13-inch baking dish, combine the cooked beef mixture with the uncooked rice, both soups, beef broth, Italian seasoning, paprika, salt, and pepper. Give it all a really good stir to make sure everything is evenly distributed. If you're adding vegetables or mushrooms, fold them in now.
Cover the dish tightly with aluminum foil and bake for 45 minutes. The rice should absorb most of the liquid and become tender. Remove the foil, sprinkle both cheeses evenly over the top, then bake uncovered for another 10-15 minutes until the cheese is melted and bubbly.
Let the casserole stand for about 5 minutes before serving - this gives the rice time to absorb any remaining liquid and makes it easier to serve. Dish it up while it's still hot and enjoy that cheesy, comforting goodness!
