Grandma Bettys Blueberry Pie with Lattice Crust

Instructions:

1. Combine flour and salt in food processor. Pulse in cold butter until pea-sized crumbs form. Slowly add ice water and vinegar, pulsing until dough just comes together. Divide in half, flatten into discs, wrap in plastic wrap, and chill for at least 30 minutes.
2. Gently toss blueberries with sugar, flour, lemon juice, and lemon zest in a large bowl. Dot with butter pieces.
3. On a lightly floured surface, roll out one dough disc into a 12-inch circle. Carefully transfer to the pie plate and trim edges, leaving a slight overhang. Crimp the edges.
4. Pour the blueberry filling into the prepared pie crust.
5. Roll out the remaining dough disc into a 12-inch rectangle. Cut into ½-inch strips using a pastry cutter or knife. Weave the strips over the filling to create a lattice pattern. Trim and crimp the edges of the lattice to seal with the bottom crust.
6. Place the pie in the refrigerator for 15 minutes.
7. Whisk together the egg and milk (or cream). Brush the lattice crust with the egg wash, then sprinkle generously with coarse sugar.
8. Preheat oven to 400°F (200°C). Place pie on a baking sheet lined with parchment paper. Bake for 15 minutes, then reduce heat to 375°F (190°C) and continue baking for 40-45 minutes, or until the crust is golden brown and the filling is bubbling. If the crust starts to brown too quickly, tent with foil.
9. Let the pie cool completely on a wire rack before slicing and serving. This is crucial – the filling will thicken as it cools.