Ground Beef Casserole

I have several new recipes, and haven't updated in ages. This one is really good, and Elise actually loves it!

1 lb. ground beef
1 onion, finely chopped
1 can cream of mushroom soup
1 cup Minute Rice
1 tsp oregano
1 tsp thyme
2 tsp sugar
1 tsp garlic salt
1 can diced tomatoes
6 slices of American cheese

Fry meat & chopped onion. Drain fat. Add remaining ingredients and cook over low heat for about 10 mins. Spread in 9x13 dish and place cheese slices on top. Let cook on 350 degrees until cheese is melted (about 10-15 minutes).