Into food processor, process cookies into crumbs, dump onto a bowl

Preheat oven to 400 F

Dilute cornstarch in water, set aside

Melt butter, then stir into cookie crumbs, dump some into spring form pan, reserve some about 4 tbsp for topping, mix in sugar, set aside

Bake crust for 5 mins

While crust is baking, bring blueberries in water to boil, cook for 5-8 mins, then stir in cornstarch solution, take off from heat

Take out crust from the oven, let it cool to room temperature

Beat cream cheese, sour cream, sugar, and essence until creamy, then beat in eggs one at a time

Mix in flour, divide batter into two bowls

Into one bowl, add in some of the blueberry filling, reserving 3 tbsp for topping, mix to combine well

Spoon white batter onto crust, followed with blueberry batter, alternating one another

Bake for 30-35 mins, take cheesecake out

Spread reserved blueberry, then sprinkle top with reserved cookie crumbs

Continue baking for another 10-15 mins (center should still be somewhat jiggly)

Cool to room temperature before chilling overnight