Strawberry-Rhubarb Filling
3 cups fresh strawberries , hulled and sliced
3 cups fresh rhubarb , trimmed and cut into 1-inch pieces
3/4 cup granulated sugar
2 teaspoons lemon juice
1/4 teaspoon vanilla extract
3–4 tablespoons quick-cooking tapioca
2 tablespoons unsalted butter , cut into small pieces
INSTRUCTIONS
Remove dough from refrigerator; let stand at room temperature to soften slightly, about 10 minutes. Heat oven to 400 degrees. Toss fruit with sugar, lemon juice, vanilla extract, and tapioca; let stand for 15 minutes.
Roll larger dough disk on lightly floured surface into 12-inch circle, about 1/8-inch thick. Transfer and fit dough into 9-inch Pyrex pie pan, leaving dough that overhangs the lip in place. Turn fruit mixture, including juices, into pie shell. Scatter butter pieces over fruit. Refrigerate until ready to top with remaining dough.
Roll smaller disk on lightly floured surface into 10-inch circle. Lay over fruit. Trim top and bottom dough edges to 1/2-inch beyond pan lip. Tuck this rim of dough underneath itself so that folded edge is flush with pan lip. Flute dough in your own fashion, or press with fork tines to seal. Cut four slits at right angles on dough top to allow steam to escape. If pie dough is very soft, place in freezer for 10 minutes before baking.
Place pie on baking sheet; bake until top crust is golden, 20 to 25 minutes. Reduce oven temperature to 350 degrees and continue to bake until juices bubble and crust is golden brown, 30 to 40 minutes longer.
Transfer pie to wire rack; let cool to almost room temperature so juices have time to thicken, from 1 to 2 hours.