Strawberry and Banana Jello Salad

3 - 3 ounce packages of strawberry jello
2 packages of frozen strawberry halves (substitute fresh strawberries in season)
1 can crushed pineapple (do not drain)
4 mashed bananas (do not puree)
3 cups hot water
1 pint sour cream

Dissolve the jello in the hot water. Add the fruits and mix. Oil a 9x13 casserole dish. Pour in half the mixture and put in freezer to harden. Mix the other half of the jello and fruit with the sour cream. Pour on top of hardened jello and refrigerate to set.