Blueberry Pie - #InTheKitchenWithKat

INGREDIENTS:
Filling ingredients:
6 cups (about 2 1/4 pounds ) fresh or frozen blueberries, rinsed and stems removed (if using frozen, defrost and drain first)
1 teaspoon finely grated lemon zest
1 tablespoon lemon juice
1/4 cup (about 30g) cornstarch, all-purpose flour, or quick-cooking tapioca
1/2 cup sugar (100g)
1/2 teaspoon cinnamon
Egg wash ingredients:
1 egg
1 tablespoon milk