Place the flour, sugar, and salt in the bowl of a food processor fitted with an 's' blade. Pulse the mixture a few times until blended together.

Add the shortening to the food processor and pulse once. Add the cubes of butter, one at a time, pulsing a few times after the addition of each cube.

With the processor running, drizzle in the ice water until the mixture starts to form into large clumps. Do not add too much water. Dough should not be sticky or wet, but should come together to form a nice dough.

Only 2/3 of the dough is needed for the crust. Wrap and freeze the remaining dough for another use.

Roll the dough into a ball, flatten a bit, and place in between two sheets of parchment paper. Roll to a circle that is 11⁄2-2 inches larger in circumference than your pie dish. Place the sheet of dough over the top of your pie dish and remove parchment paper. Press the dough in to fit the bottom and sides of the dish. There should be a little bit of dough left hanging over the edges. Trim dough around the edge of the pie and crump.

Preheat the oven to 350°F.

Combine the sugar, flour, salt, eggs and sour cream in a mixing bowl and whisk until combined.

Add the blueberries to the pie crust and disperse evenly. Pour the custard mixture over the blueberries.

Add the sugar, brown sugar and flour to a mixing bowl and combine.

Using a fork or pastry blender, cut the butter into the dry ingredients until the mixture resembles small peas.

Sprinkle the crumble evenly over the top of the pie.

Bake for 50-55 minutes or until the pie is golden brown on top. Cool on a wire rack.

Serve warm, if desired, with vanilla ice cream.

Store covered in the refrigerator.