2 1/2 cups all-purpose flour
1 rounded tablespoon sugar
1 rounded teaspoon salt
1/2 cup chilled unsalted butter, cut into pieces
2/3 cup frozen vegetable shortening, cut into pieces
4 to 6 tablespoons ice water
2 teaspoons apple cider vinegar
3 cups Concord grapes
1 cup sugar
3 tablespoon flour
Dash of salt
1/2 teaspoon grated lemon peel
2 tablespoons butter
For crust, combine flour, sugar and salt in food processor, and pulse to blend. Add butter and shortening and cut into flour mixture. When the mixture resembles coarse meal, transfer it to a large bowl. In a small bowl, combine the cider vinegar with four tablespoons of ice water. Pour over flour mixture. Stir with fork until moist clumps form, adding an additional two tablespoons ice water if necessary. Separate dough into two balls, and flatten them into disks. Wrap in plastic and chill for 30 minutes.
Slip skins from grapes. Bring pulp to a boil. Reduce heat and simmer for 5 minutes. Press through sieve to remove seeds. Add skins. Mix sugar, flour, salt, and lemon peel together, and add the grape pulp. Place one pie crust into a 9â€³ pie pan and pour in the grape mixture. Lay several small pieces of butter over the filling and cover with the top crust. Bake at 400 for about 45 minutes.