Preheat the oven to 350*F. Roll out the pastry and line a 9-inch pie pan; set aside.
In a medium saucepan, whisk the egg until frothy. Whisk in the flour. Add the brown sugar, corn syrup, water, vanilla, mace, and salt and mix well. Over medium-high heat, bring the mixture just to a full rolling boil, stirring occasionally. Remove from the heat and let cool to room temperature. (The filling will be slightly thickened.)
While the filling is cooling, prepare the crumb topping. In a medium mixing bowl, combine the flour, brown sugar, vanilla, cream of tartar, baking soda, mace, and salt. Using a pastry blender or pastry fork, cut in the cold butter until the topping resembles coarse crumbs. Pour the cooled filling into the pastry shell. (The pastry will be only half full but the pie will rise as it bakes.) Sprinkle with the crumb topping. Cover the edges of the pastry with foil to prevent overbrowning. Bake for 25 minutes, then remove the foil and bake for an additional 20 minutes or until the top is a deep, golden brown. The filling will be a bit soft but will firm up as it cools. Remove to a rack to cool completely before cutting.

CLASSIC CRISCO CRUST

Amount Measure Ingredient -- Preparation Method
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8-, 9- or 10-inch Single Crust
1 1/3 cups all-purpose flour
1/2 teaspoon salt
1/2 cup Crisco Shortening
3 tablespoons cold water

FOR PIE DOUGH, spoon flour into measuring cup and level. Combine flour and salt in medium bowl. Cut in Crisco using pastry blender (or 2 knives) until all flour is blended to form pea-size chunks. Sprinkle with water, 1 tablespoon at a time. Toss lightly with fork until dough will form a ball.
FOR SINGLE CRUST, press dough between hands to form 5- or 6-inch "pancake." Flour lightly on both sides. Roll between sheets of waxed paper on dampened countertop until 1 inch larger than upside-down pie plate. Peel off top sheet. Flip into pie plate. Remove other sheet. Fold dough edge under and flute.

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