Creating a Blueberry Crumble Cheesecake Pie is a delightful journey. Follow these steps for a successful outcome:

1. Preheat Oven: Begin by preheating your oven to 325°F (160°C).
2. Prepare the Crust: In a mixing bowl, combine graham cracker crumbs, melted butter, and sugar. Stir until everything is well combined. Press the mixture into the bottom of a 9-inch pie plate. Bake for 10-12 minutes until golden. Allow it to cool.
3. Make the Cheesecake Filling: In a large bowl, beat the softened cream cheese with a handheld mixer or a stand mixer until smooth and free of lumps. Gradually add granulated sugar and mix until combined. Add the eggs, vanilla extract, and lemon juice, mixing until smooth and well combined.
4. Add Blueberries: In a separate bowl, gently mix the blueberries with sugar and cornstarch, ensuring they are well-coated. Fold blueberries into the cheesecake filling carefully to avoid mashing them.
5. Fill the Crust: Pour the cheesecake and blueberry mixture into the prepared graham cracker crust, smoothing it out on top.
6. Bake: Place the filled pie in the preheated oven and bake for 35-40 minutes. The edges should appear set, while the center will remain slightly jiggly.
7. Prepare the Crumble Topping: In another bowl, combine oats, flour, brown sugar, and cinnamon. Mix in softened butter until crumbly. Sprinkle the crumble topping evenly over the cheesecake after removing it from the oven.
8. Final Bake: Return the pie to the oven for an additional 10-15 minutes, until the crumble is lightly golden.
9. Cool: Remove from the oven and allow the pie to cool at room temperature for about an hour. Then, refrigerate for at least 3 hours or overnight for best results.
10. Serve: Once set, slice and serve with a dollop of whipped cream if desired!