Strawberry Congealed Salad

1 (6 oz.) strawberry gelatin
1/2 c. boiling water
1 (10 oz.) frozen strawberries
1 (13 oz.) crushed pineapple (partly drained)
2 mashed bananas
1 pt. sour cream

Dissolve strawberry gelatin in boiling water. Add strawberries, pineapple and bananas. Stir well. Pour 1/2 mixture into casserole dish and congeal. Spread sour cream over the top of congealed salad. Pour remaining mixture over this and congeal.