We love rhubarb not just because it signals spring, but also because its tart flavor and silky texture produce great pies.
Preheat oven to 400°. Unwrap larger disk of Double-Crust Pastry Dough. Roll out and fit into a deep-dish 9-inch pie pan. Trim dough ½ inch beyond rim of pan and set aside.
Roll out remaining dough to ⅛-inch thickness and cut into strips about ¾ inch wide. Cover with a damp towel and set aside.
Mix sugar, cornstarch, and salt. Add rhubarb, orange zest, and orange juice; toss until well mixed. Turn into pastry shell and dot with butter.
Arrange dough strips over pie in a lattice pattern. Fold excess bottom crust up and over lattice edges and crimp. Brush dough with cream and sprinkle with sugar. Bake until crust is golden brown and filling is thick and bubbly, 50–60 minutes.
In a medium-size bowl, whisk together flour, sugar, and salt until well combined.
Sprinkle butter over flour mixture, and use your fingers to work it in (rub your thumb against your fingertips, smearing the butter as you do). Stop when the mixture looks like cornmeal, with some pea-size bits of butter remaining.
Sprinkle 6 tablespoons ice water on top, and stir with a fork until dough begins to come together. If needed, add more ice water, a tablespoon at a time.
Turn out onto a lightly floured surface and knead three times, or just enough to make a cohesive dough—don’t overmix!
Gather into a ball; then divide into two pieces, one slightly larger than the other. Press each piece into a disk and wrap in plastic. Refrigerate 30 minutes.