Directions

Dough
1. In a large bowl combine flour and salt.
2. Using a pastry cutter, add cold butter, cutting into a coarse, crumbly, pea size mixture.
3. Tossing with a fork, drizzle in vinegar, then iced water, a tbsp at time. Form with hands until dough comes together. 
4. Form dough into 2 x 1” thick disks. Seal well in plastic wrap and chill for a minimum of 2 hours.

Filling and Assembly:
1. Pre-heat oven to 450F/232C and line a large baking sheet with parchment paper.
2. Whisk the egg and milk together and set aside.
3. In a large bowl, gently mix the blueberries, sugar, flour, lemon zest, lemon juice and cinnamon. If using frozen blueberries, allow to thaw partially.
4. Divide one of the pastry disks into 5 portions. Keep the other pastry disk sealed and refrigerated.
5. Working one at a time on floured surface, roll out a portion of pastry into 5” round. Trim any rough edges. Lightly brush edges of the pastry round with egg wash.
6. Fill one half of pastry round with 3-4 tablespoons of blueberry mixture and dot with 2 pieces of cubed butter. 
7. Fold the filled pastry round over and seal the edges firmly together, then crimp or seal with a fork. Place on a lined baking sheet, brush with egg wash, score 2 small slits and sprinkle with coarse sugar. 
8. Repeat with the remaining pastry portions and then the second chilled pastry disk.
9. Bake in the middle rack of a 450F oven for 18-20 minutes, until golden brown.