1 onion, finely diced
1 (10.75 ounce) can condensed cream of mushroom soup
1 cup instant rice
1 (14.5 ounce) can diced tomatoes
1 tablespoon garlic powder
1 teaspoon dried thyme
1 teaspoon dried oregano
2 teaspoons white sugar
6 slices American cheese
Preheat oven to 350 degrees F (175 degrees C). Place ground beef and onions in a large, deep skillet. Cook over medium high heat until beef is evenly brown. Drain any excess fat. Add the soup, rice, tomatoes, garlic powder, thyme, oregano and sugar. Mix well and cook over medium heat for 10 minutes. Place in a 9x13 inch casserole dish. Top with cheese slices and bake for 15 to 20 minutes or until cheese is bubbling and browning.