My Family's Favorite Recipes for Goumi Berry Pie

Ingredients

• 1 ½ cups all-purpose flour
• ½ cup unsalted butter, cold and cubed
• 2 tablespoons granulated sugar
• ½ teaspoon salt
• 3-4 tablespoons ice water
• 2 cups fresh goumi berries
• ¾ cup granulated sugar
• 2 tablespoons cornstarch
• 1 tablespoon lemon juice
• ½ teaspoon vanilla extract
• 1 teaspoon ground cinnamon (optional)
• 1 large egg (for egg wash)
• 1 tablespoon milk