Adding cocoa powder to a classic pie dough creates a unique chocolate crust that pairs perfectly with the sweet, juicy fruit nestled inside. If you aren't a fan of lattice crusts, you can use a small cookie cutter to cut out decorative pieces of dough to simply place on top instead.

To prepare crust: Combine whole-wheat flour, all-purpose flour, cocoa, 1/4 cup sugar and 1/4 teaspoon salt in a food processor. Pulse to combine. Add 8 tablespoons cold butter and oil. Pulse until the butter forms pebble-size pieces. Add 1/2 cup water and pulse until the mixture starts to come together, taking care not to overmix. (If you grab a handful, it should hold together in your palm. If the mixture is too dry, add more water 1 tablespoon at a time.) Divide the dough in half. Press each half into a disk and wrap tightly in plastic wrap. Refrigerate for at least 2 hours and up to 3 days.

Preheat oven to 375°F. Coat a 9-inch pie pan (not deep-dish) with cooking spray. Roll 1 disk of dough on a lightly floured surface into an 11-inch round. Transfer to the prepared pan and lightly press it in. Tuck any overhanging edges under. Crumple a piece of parchment paper, then lay it out flat over the bottom of the crust. Fill the paper with pie weights, dried beans or uncooked rice. Bake until golden around the edges, about 20 minutes. Remove the paper and weights. Let the crust cool for 30 minutes.

Meanwhile, prepare filling: Mix cherries, berries, sugar, flour, lemon juice, vanilla, cinnamon and salt in a large bowl.

Roll the second disk of dough into a 12-inch square. Cut into about twelve 1-inch-wide strips.

Add the filling to the crust. Dot it with butter.

To form a lattice: Lift off every other strip of the dough and lay them on top of the pie, leaving about a 1-inch gap between strips. Fold back the first, third and fifth strips all the way to the edge of the pie. Place a strip of dough across the unfolded strips, about 1 inch from the edge. Place the folded strips back over that crosswise strip. Fold back the second, fourth and sixth strips to the crosswise strip. Place another strip crosswise, about 1 inch from the first. Unfold the strips over that second crosswise strip. Continue alternately folding and placing until the top is covered with woven strips. (You may not use them all.) Trim any uneven edges and tuck the overhanging crust under the bottom crust. Crimp or pinch the edge to seal the top and bottom crusts together. Freeze the pie for 10 minutes.

Brush the lattice with egg, then sprinkle with demerara sugar. Place the pie on a rimmed baking sheet. Bake for 35 minutes. Cover the edges with strips of foil and continue baking until the filling is bubbling vigorously and the crust appears set, 20 to 25 minutes more. Let cool to room temperature on a wire rack, about 3 hours.

Refrigerate dough (Step 1) for up to 3 days.

9-inch pie pan (not deep-dish), parchment paper, pie weights (or dried beans or uncooked rice)