Ingredients
4cupsall-purpose flour,spoon & leveled
1½tspsalt
1tspgranulated sugar
1¾cupunsalted butter,very cold, cubed
¾cupice cold water
1large egg,(lightly beaten with 1 tbsp milk)
coarse sugar,for sprinkling on top, optional
4cupsfresh strawberries,hulled and chopped
4cupsfresh blackberries,halved
½cupgranulated sugar
¼cupcornstarch
1tbsplemon juice
1tsppure vanilla extract
pinchsalt
Preparation
Mix the flour, salt, and sugar together in a large bowl. Add the butter. Using a pastry cutter, a food processor, or two forks, cut the butter into the mixture until there are pea-sized crumbles with a few larger crumbs of fat.
Drizzle the cold water in, 1 tablespoon at a time, and stir after every tablespoon added. Stop adding water when the dough begins to form large clumps.
Transfer the pie dough to a floured work surface. Using floured hands, fold the dough into itself until the flour is fully incorporated into the butter pieces. The dough should come together easily and should not feel overly sticky.
Form dough into a ball. Divide dough in half. Flatten each half into 1-inch thick discs. Wrap each tightly in plastic wrap.
Refrigerate for at least 2 hours (and up to 5 days) or freeze for up to 3 months. Thaw overnight in the fridge before using.
Gently mix all of the filling ingredients together in a large bowl. Set aside.
Preheat oven to 375 degrees F.
Remove 1 disc of pie dough from the refrigerator. Keep the other in the refrigerator. Roll the dough out into a rectangle or oval shape.
Dough should be about ⅛-inch thick. Make sure to turn the dough about a quarter turn after every few rolls. Carefully place the dough (with parchment/silicone baking mat) onto a large rimmed baking sheet.
Spoon filling evenly on top of crust, leaving any excess liquid in the bowl. Leave a bare 1-inch border around the edges.
Roll out the 2nd pie dough disc in the same-ish shape as the 1st. Drape over filling, then seal the top and bottom crusts together around the edges.
Flute the edges or crimp with a fork. Cut slits into the top of the crust, then brush with a thin coating of egg wash. Sprinkle with coarse sugar, if desired.
Bake the slab pie for about 45 to 55 minutes until the crust is golden brown and the filling is bubbling. Remove from the oven and, if serving as hand-held bars, allow to cool completely in the pan set on a wire rack.
If serving on plates, allow to cool for at least 45 minutes in the pan set on a wire rack.
Cover leftovers tightly and store in the refrigerator for up to 3-4 days.
