Mix together all of the se ingredients and press half of the mixture on the bottom of a 9 x 13 inch pan.
Spread the diced rhubarb on top of the crust. Boil the sugar, water, and cornstarch until thick. Add the almond flavoring, then the pie filling, and spoon the mixture over the rhubarb. Sprinkle the remaining crust mixture over it, then the nuts. Bake for 45 minutes at 350 degrees F. Serve warm with whipped cream.