Slow cooker chicken and rice

1 1/2 cup long grain rice
4 cups water
3 chicken bouillon cubes
1 can cream of chicken soup
1 medium onion chopped
16 oz bag of frozen broccoli
2 cups chopped cooked chicken (I used canned)
1/4 tsp garlic powder
1 cup grated cheddar cheese (I would add more next time, but I LOVE cheese)
salt and pepper to taste

Combine all ingredients in slow cooker. Cook on high 3-4 hours.