For the pastry:

1. Add flour and salt to a food processor. Pulse to combine.
2. Add the cubed butter, and pulse until crumbs are pea-size.
3. In a medium-size bowl, whisk sour cream, egg yolk, and ice water, then add it to the food processor. Pulse just until it comes together.
4. Form into a ball, wrap in plastic wrap and flatten into a disk. Refrigerate for 1 hour.

For the filling:

1. Toss haskaps, sugar, lemon zest and juice, cornstarch, and salt in a bowl.

Assembly:

1. Line a baking sheet with parchment paper (I used the reusable Cookina baking sheet).
2. On a lightly floured surface, roll out the dough to about 1/4-in. thickness. Cut 12 rounds using a 4-inch round cutter, re-rolling the dough with the scraps. Refrigerate on the prepared baking sheet for about 15 minutes.
3. In the meantime, preheat the oven to 375° F (190° C).
4. Scoop 2 Tbsp of haskap mixture onto the center of 6 rounds of dough.
5. Whisk egg and 1 tsp water in a small bowl for egg wash and brush edges.
6. Place another round over the filling, pressing to seal. Crimp the edges with a fork, then refrigerate on the prepared baking sheet for about 20 minutes.
7. Brush with the remaining egg wash. Cut a small X on top of each hand pie. Sprinkle with coarse sugar.
8. Bake until filling is bubbling and pies are golden brown, about 18-20 minutes.
9. Let cool on a rack for 15 minutes, and enjoy!