Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
                        ***CRUST***
   2      cups          all-purpose flour
   1      teaspoon      salt
   1      stick         chilled unsalted butter -- sliced
     1/3  cup           chilled vegetable shortening
     1/3  cup           sugar
   1      large         egg -- well beaten
   1      teaspoon      distilled white vinegar
   2      tablespoons   ice water -- approximately
                        ***FILLING***
     2/3  cup           packed dark brown sugar
     1/4  cup           fresh lemon juice
   1      tablespoon    vanilla extract
   1 1/4  teaspoons     cinnamon
     1/2  teaspoon      salt
     1/2  stick         unsalted butter
   4      pounds        tart green apples -- cut 1/4", peeled
                        ***STREUSEL***
     3/4  cup           all-purpose flour
   4 1/2  tablespoons   sugar
   2      tablespoons   unsalted butter
   3                    Heath (1.4 oz) toffee bars -- chopped
   1      large         egg beaten with:
   2      tablespoons   water -- (glaze)

Preparation:

For crust, combine flour and salt in medium bowl. Cut in butter and shortening with fork till mixture resembles coarse meal. Stir in sugar, egg and vinegar. Mix in just enough ice water, 1 tbs. at a time, to form dough that holds together. Divide dough in half, flatten each half into disc, wrap each in plastic and chill 4 hours. For filling, combine ingredients (except apples and butter), add apples and toss to coat. Melt butter in large skillet over medium high heat. Add apple mixture and cook till apples are slightly softened, about 10 minutes. Cover and chill. Preheat oven to 350F. On a floured surface, roll out 1 dough piece to 14" diameter. Transfer to a 9" deep dish glass pie dish. Trim edges leaving 1/2" overhang. Fold overhang under and let rest on rim of dish. Line crust with foil. Fill with dried beans and bake 10 minutes. Remove beans and foil. Bake crust till crust has set but has no color, about 5 minutes. Remove and cool, leave oven on. For streusel, combine flour and sugar in bowl. Using fork mix in butter till coarse meal forms. Stir in toffee. On lightly floured surface, roll out 2nd dough disc to 14" diameter. Mound apple filling in prebaked pie crust. Sprinkle streusel over filling. Top with dough round. Trim dough leaving 1/2" overhang. Gently pinch crust edges together to seal. Brush pie with glaze. Cut 5 slits in pie top to allow steam to escape. Bake until crust is golden and apples are tender, about 55 minutes. Cool pie 1 hour. Serve with good quality vanilla ice cream.