Creamy Chicken and Rice

4 cups COOKED rice
1/2 cup butter or margarine, divided
1/4 cup all-purpose flour
2 cups milk
2 tsp. chicken bouillon granules (or 2 bouillon cubes)
1/2 to 1 tsp. seasoned salt
1/2 tsp. garlic powder
1/4 tsp. pepper
4 to 5 cups cubed COOKED chicken
12 ounces process American cheese, cubed
2 cups (16 oz.) sour cream
1 1/4 cups crushed butter-flavored crackers (about 32)

Spread rice into a greased shallow 3-qt. or 13in x 9in x 2in baking dish; set aside. In a saucepan, melt 1/4 cup butter; stir in flour until smooth. Gradually add milk, bouillon, seasoned salt, garlic powder and pepper. Bring to a boil; cook and stir for 2 minutes or until thickened and bubbly. Reduce heat; add chicken, cheese and sour cream; stir until the cheese is melted. Pour over rice. Melt the remaiining butter; toss with cracker crumbs. Sprinkle over casserole. Bake, uncovered, at 425 F for 10-15 minutes or until heated through.