Hamburger/Green Bean Casserole

1 1/2 lbs ground beef
1 cup chopped onions
1 t salt
1/8 t pepper
1/8 t thyme
2 or 3 cans (16 oz) green beans, drained
1 can (10 1/2 oz) cream of mushroom soup
1/2 cup sour cream

Brown ground beef and onions. Add the rest of the ingredients, stirring until well mixed. Pour into a 2 qt casserole dish.

Bake at 350 degrees for 30 minutes or until browned.