Preheat your oven to 350°F (175°C).
In a skillet over medium heat, brown the ground beef with the chopped onion until the beef is no longer pink. Drain excess fat.
Stir in garlic powder, salt, and black pepper.
In a 9x13 inch baking dish, combine the soups, uncooked rice, water, and the cooked beef mixture. Mix until everything is evenly blended.
Cover the dish tightly with foil.
Bake in the preheated oven for 60 minutes or until the rice is tender.
If you're adding cheese, remove the foil in the last 10 minutes of baking and sprinkle cheese on top, then return to the oven uncovered.
Let it rest for 5 minutes before serving.