Combine first 4 ingredients in a large heavy-duty, zip-top plastic bag; add fish. Seal bag; gently turn bag to coat fish. Marinate in refrigerator at least 15 minutes.
While fish marinates, combine sour cream, hot sauce, and chili powder in a small bowl; set aside.
Remove fish from marinade, discarding marinade. Place fish on rack of a broiler pan coated with cooking spray. Broil 5 1/2 inches from heat (with electric oven door partially opened) 8 minutes or until fish flakes easily when tested with a fork. Serve with chili cream.