Creating the Lemon Blueberry Crumble Cheesecake is simple if you follow these steps:

1. Preheat Your Oven: Preheat to 325°F (160°C). Grease a 9-inch springform pan.
2. Make the Crust: In a bowl, mix graham cracker crumbs, melted butter, and granulated sugar until combined. Press the mixture evenly into the bottom of the springform pan.
3. Prepare the Cheesecake Filling: In a large mixing bowl, beat the softened cream cheese and granulated sugar until smooth. Add eggs one at a time, mixing well after each addition.
4. Add Residual Ingredients: Stir in the sour cream, lemon juice, lemon zest, and vanilla extract until well combined.
5. Assemble the Cheesecake: Pour the cheesecake mixture over the prepared crust.
6. Prepare the Blueberry Topping: Combine blueberries, granulated sugar, and cornstarch in a small saucepan over medium heat. Cook until the blueberries begin to breakdown, approximately 5-7 minutes.
7. Add Blueberries: Gently pour the cooked blueberry mixture over the cheesecake batter, using a knife to swirl it slightly.
8. Bake: Place the cheesecake in the oven to bake for 50-60 minutes, or until the center is set and does not jiggle.
9. Prepare the Crumble Topping: While the cheesecake is baking, mix the oats, flour, brown sugar, and cinnamon in a bowl. Add the softened butter and mix until crumbly.
10. Top with Crumble: Remove the cheesecake from the oven and sprinkle the oatmeal crumble mixture generously on top.
11. Bake Again: Return the cheesecake to the oven for an additional 15-20 minutes until the crumble is lightly golden.
12. Cool Down: Turn off the oven, crack the door, and let the cheesecake cool in the oven for one hour. Then move to a wire rack to cool completely.
13. Chill: Refrigerate the cheesecake for at least 4 hours, preferably overnight, to set properly.

These straightforward instructions will lead you to the ultimate Lemon Blueberry Crumble Cheesecake, showcasing all its deliciousness with ease.