I changed up a great recipe I found online and used an old family pie crust recipe (instead of the one the recipe called for) and it turned out SO yummy! It looks like there is a TON of cornstarch, but my pie turned out a bit wet at first, so make sure you let it set for a bit before you slice into it.
Never Fail Pie Crust (this is an old family recipe... works GREAT every time)
3 cups sifted flour
1 tablespoon sugar
1 teaspoon salt
1 cup chilled vegetable shortening
1 egg, beaten with enough milk added to make 1/2 cup
3 1/2 cups 1/2-inch-thick slices trimmed rhubarb (1 1/2 pounds untrimmed)
1 16-ounce container strawberries, hulled, halved (about 3 1/2 cups)
1 tablespoon Grand Marnier (or any other orange flavored liqueur)
1/2 cup (packed) golden brown sugar
1/2 cup sugar
1/4 cup cornstarch
1 teaspoon ground cinnamon
1/4 teaspoon salt
1 large egg yolk beaten to blend with 1 teaspoon water (for glaze)
Make crust: Combine flour, sugar and salt in large bowl. Cut in shortening with pastry blender until the mixture resembles pea-sized pieces. Add egg mixture and mix just until combined. Pat on a floured surface into a large disc of dough. Cut dough in half. Flatten each half into disk. If not using immediately, wrap in plastic and put in refrigerator.
Make filling: Preheat oven to 400°F. Put rhubarb and strawberries in a large bowl and pour Grand Marnier over them to let soak for 10 minutes. Add next 5 ingredients. Toss gently to blend.
Assemble Pie: Roll out 1 dough disk on floured work surface to 13-inch round. Transfer to 9-inch-diameter pie dish. Trim excess dough, leaving 3/4-inch overhang. Roll out second dough disk on lightly floured surface to 13-inch round. Cut into fourteen 1/2-inch-wide strips. Spoon filling into crust. Arrange 7 dough strips atop filling, spacing evenly. Form lattice by placing remaining dough strips in opposite direction atop filling. Trim ends of dough strips even with overhang of bottom crust. Fold strip ends and overhang under, pressing to seal. Crimp edges decoratively.