Ingredients

Crust:
2 cups all-purpose flour, plus additional flour as needed, up to 1/4 cup
1/2 cup cake flour (recommended: Soft As Silk)
3 teaspoons sifted powdered sugar
1/2 cup butter-flavored shortening (recommended: Crisco)
1/4 cup salted butter
Pinch salt
1 egg
2 teaspoons vinegar
1/4 cup ice cold water
Filling:
2 1/2 cups chopped red rhubarb, fresh
2 1/2 cups de-stemmed, washed and cut strawberries (in larger pieces)
1 1/2 cups sugar (1 1/4 cups for high altitude)
2 tablespoons minute tapioca
1 tablespoon all-purpose flour
1/2 teaspoon lemon zest
1/2 teaspoon lemon juice
1/2 teaspoon ground cinnamon
1 teaspoon vanilla extract
3 tablespoons butter, cubed small
1 egg white beaten with 1 teaspoon water
Large granule sugar