Strawberry rhubarb pie is the flavor combination you have been waiting for. It has the perfect flavor combination of sour, sweet, juicy and buttery flavors and minimal prep work.
Make it with a food processor: Place flour, salt, sugar, and butter in a food processor and pulse 4-5 times. Pea-sized butter flakes should still be visible. Add one tablespoon water after another and pulse 1-2 times after every tablespoon. Stop adding water when the dough starts to clump.
If you don't have a food processor, then make it with a pastry cutter or two forks instead: In this case mix together flour, salt, and sugar in a large mixing bowl. Then add butter and cut it into the mixture until it resembles coarse meal with pea-sized butter flakes. Then add water little by little until the texture starts to clump.
Divide pie crust into two halves and form 1 - 1.5 inch thick discs without kneading. Cover tightly with plastic wrap and refrigerate at least 2 hours or up to 2 days.
Stir rhubarb, strawberries, both sugars, salt, and vanilla* together in a large bowl and set aside.
Preheat oven to 375°F (190°C).
On a lightly floured surface roll out the first dough disc into a 12-inch circle. Transfer to a 9-inch pie dish. The edges of the pie crust should hang out of the baking form.
Drain filling and discard all of the liquid. Add cornstarch and stir to combine. Add filling to the pie dish. Then cut butter into small pieces and put on top of the filling.
Then roll out the second dough disc and place on top of the filling. Decorate to your preference. If you cover the filling with a dough circle, then cut a few slits in the top layer that the steam can escape throughout baking. If you want to arrange a lattice, then cut top layer into strips and lay strips over and under one another carefully. Seal and flute the edges.
If desired, brush with egg wash (1 large egg and 1 tbsp water), egg yolk, egg white, or melted butter, and sprinkle with sugar.
Bake for about 45 minutes until golden brown. Cover with parchment paper after 30 minutes to prevent it from heavy browning. Let cool to room temperature and transfer to the refrigerator. Chill for about 3 hours to allow the filling thicken up. Store in an airtight container in the refrigerator for up to 3 days.
Enjoy warm or cold with ice cream and fresh fruits.
*First, cut off the straight end of the vanilla bean. Then place the tip of your sharp knife below the curled end and cut the vanilla bean through the middle of the bean lengthwise. Although you don't need to cut it all the way through, it's ok when you do so. Then open the vanilla bean and scrape out the flavorful seeds with the back of your knife. Then just use the seeds.
You could consider these substitutions and additions
Add in 1 cup (150g) sweet or tart apples and adjust the strawberries to 1 cup (150g). Apples and strawberries are amazing together.
Put in 1/2 teaspoon (2g) of cinnamon powder to give the rhubarb pie a hint of spiciness.
Pour 1 tablespoon (15g) of lemon juice into the fruit mixture. It will add a tangy flavor that is so scrumptious.
Toss in 1/3 cup (113g) of walnuts. It's even more delicious if the walnuts are toasted. They give the strawberry rhubarb pie filling a nice crunch.