Let's Begin!

Crust

• Whisk together the flour, sugar, and salt in a large bowl. Add the butter to the dough and use your fingers to work the butter into the dough until the mixture resembled crumbs.
• Add the sour cream to the mixture and mix in with a fork. Gather the dough into a ball with your hands and flatten it into a disk shape.
• Wrap the dough with plastic wrap and chill for at least an hour before rolling it out.

Filling

• In a medium-sized bowl, gently toss the plum slices with the sugar, cinnamon, lemon juice, orange zest, and cornstarch.

Let's Assemble and Bake!

• Preheat oven to 375℉. And line a baking sheet with parchment paper.
• Lightly flour a clean surface and roll out the dough to a 13-inch round of even thickness.
• Place the rolled-out dough in the center of the prepared baking sheet. Arrange the plum slices in a circular pattern, starting from 1 1/2 to 2 inches from the outside edge of the dough, working your way into the center.
• Fold the edges of the pie crust up and over so that circle of the filling is visible.
• Whisk together the egg and water in a small bowl. Brush on the exposed pastry crust with a pastry brush. Sprinkle with some coarse sugar.
• Bake for 40-50 minutes, or until the crust is lightly browned and the filling is bubbly. Cool on a rack for an hour before serving.
• Serve and enjoy with family and friends!