Blueberry-Blackberry Pie

Ingredients

for the Pie Crust

2 cups (500 mL) Robin Hood® Original All Purpose Flour
¾ tsp (4 mL) salt
1 cup (250 mL) Crisco® All-Vegetable Shortening
1 egg
2 tbsp (30 mL) cold water
1 tbsp (15 mL) white vinegar

for the filling

6 cups fresh or frozen blueberries and blackberries

1 cup sugar
1/4 cup cornstarch
1 tbsp lemon zest

Directions

Preheat oven to 350°.
Roll out a disk of dough on a lightly floured surface to a 13" round. Transfer round to a parchment-lined baking sheet and chill while you roll out remaining disk of dough to a 13" round (about ¼" thick). Stack on top of the first round of dough, separating with a sheet of parchment. Chill while you prepare filling.
Combine granulated sugar, cornstarch, lemon zest, and salt in a large bowl, rubbing together with your fingertips to release oils in zest and evenly distribute ingredients. Add blueberries and blackberries and lemon juice and toss to coat.
Beat egg with 1 tsp. water in a small bowl just to blend. Using your hands, or wrapping dough around a floured rolling pin if you're nervous, carefully transfer 1 round of dough to a 9" pie dish. Lift up edges and allow dough to slump down into dish. Scrape in berry filling along with any accumulated juices in bowl. Brush edge of dough with half of egg wash, then using parchment, carefully transfer remaining round of dough to pie, placing over filling.
Working your way around the circumference, press edges of dough together to seal. Crimp with a fork. Trim excess dough with kitchen shears so there is no overhang. Cut several about 3"-long slits into top of pie, avoiding edge. Brush dough with remaining egg wash; sprinkle with sugar.
Place pie pan on a foil-lined rimmed baking sheet (juices may bubble over—this is what the foil is for). Bake until crust is deep golden brown on top and bottom and juices are bubbling, about 1 ½ hours. Transfer pie to a wire rack and let sit at least 4 hours before slicing.
Do Ahead: Pie can be made 2 days ahead. Cover and chill.