Summer Berry Balsamic Pie Bars

This recipe is designed for ease of use, and throwing a pie crust together in a food processor is as easy as it gets. If you'd like to be more hands-on, whisk the dry ingredients together in a large mixing bowl and cut in the butter with a pastry cutter to achieve the same result. 

Summer Berry Balsamic Pie Bars

Serves | 12 to 18 |

If you can, let these bars cool overnight before slicing them. It's less messy and they'll hold together better if you're transporting them. Experiment with berries here: If you're not a fan of raspberries, for instance, substitute an equal amount of blackberries. 

Double Crust

• 4 cups all-purpose flour, unbleached
• 1 Tbsp granulated sugar
• 1 ½ tsp kosher salt
• 3 ½ sticks unsalted butter, chilled and cut into ½-inch cubes
• ¾ cup ice water

Filling

• 4 cups strawberries, tops removed, quartered
• 2 cups raspberries
• 2 cups blackberries (if they are large, halved lengthwise)
• ½ cup granulated sugar
• 5 Tbsp cornstarch
• 2 Tbsp lemon juice
• 2 Tbsp balsamic vinegar
• scant ½ tsp kosher salt
• 1 large egg mixed with 1 tsp water, for brushing top 
• sanding sugar or granulated sugar, to sprinkle top

| Preparation – Double Crust | Add flour, sugar and salt to the bowl of a food processor; pulse to blend. Add half the butter cubes, pulse 2 to 3 times to incorporate, then add remaining cubes. Pulse in 1-second bursts until mixture resembles coarse sand. Continue to pulse, slowly streaming ice water into the mixture until it begins to come together. Transfer to counter and knead a few times until cohesive dough forms. Divide in half, shaping each half into a 1-inch disk. Wrap each in plastic wrap and refrigerate at least 2 hours or overnight. 

Remove one disk from refrigerator and roll out on a flour-dusted surface into a rectangle large enough to fit a lipped 9-by-13-inch pan so it slightly hangs over the sides. Fold dough in thirds and transfer to pan, pressing into the sides. Place pan in refrigerator, remove second disk and roll out to approximately the same size. Using a pizza wheel, cut thick strips to lattice the top. 

| Preparation - Filling | Preheat oven to 375°F and set rack in center of oven. Add berries to a large mixing bowl; add sugar, cornstarch, lemon juice, vinegar and salt and toss until evenly incorporated. Use a slotted spoon to transfer mixture into baking pan, spreading it out evenly over surface. Pour remaining liquid evenly over the top of the berries, then top with strips of dough to form lattice. Brush top with egg wash, then sprinkle with sugar. Bake for 1 hour to 1 hour and 10 minutes, until filling is bubbling in center and crust is golden. Remove from oven and let cool completely (preferably overnight), then cut into bars and serve.