an egg wash made by beating 1 large egg with 1 tablespoon water
about 1/4 cup red currant jelly
melted
Instructions
In a large bowl blend the flour, the butter, the vegetable shortening, and the salt until the mixture resembles meal.
Add 2 tablespoons ice water, toss the mixture until the water is incorporated, adding more ice water if necessary to form a dough, and form the dough into a ball.
Dust the dough with flour and chill it, wrapped in wax paper, for 1 hour.
Roll out the dough 1/8 inch thick on a lightly floured surface, fit it into a 9-inch (1-quart) pie plate, and crimp the edge decoratively.
Line the shell with foil, fill the foil with the rice, and bake the shell in the middle of a preheated 425F.
oven for 10 minutes.
Remove the rice and foil carefully and bake the shell for 3 to 5 minutes more, or until it is pale golden.
In a large bowl stir together the sugar, the tapioca, a pinch of salt, the vanilla, the rhubarb, and the butter until the mixture is combined well and let the filling stand, stirring occasionally, for 15 minutes.
In a large bowl stir together the brown sugar, the flour, the butter, the cinnamon, the walnuts, and a pinch of salt and blend the mixture until it resembles coarse meal.
Spoon the filling into the shell, sprinkle the streusel topping around the outer 2 inches of the filling, leaving the center exposed, and brush the edge of the shell with some of the egg wash. Bake the pie on a baking sheet in the lower third of a preheated 450F.
oven for 15 minutes, reduce the heat to 350F., and bake the pie for 50 minutes to 1 hour more, or until the filling is bubbling and the rhubarb is tender.
Brush the exposed (center) portion of the filling with the jelly and let the pie cool on a rack for 2 hours.