Cook cornstarch, water & sugar until cornstarch is clear or thick. Remove from heat, add gelatin & stir well. Add blackberries & pour mixture into deep crust. Top with whipped cream.
Naomi baked this & brought it to Wayne when she, Bert, Esther, & Lowell picked and brought boxes of blackberries ready to freeze the summer of 1987. They were all so good to us -- we appreciated it.