Mix melted butter and crushed Oreo cookies in a medium mixing bowl until the cookies are moistened.
Pour the Oreo mixture into a springform pan and press the cookies evenly over the bottom and sides of the pan to form the crust.
Bake for 10 minutes. Remove from the oven and set aside to cool slightly.
Raspberry Sauce
While the crust cooks, puree the raspberries in a food processor until smooth. Strain the puree through a fine mesh sieve to remove the seeds.
Transfer the raspberry puree to a medium saucepan. Whisk in the sugar, water, and cornstarch.
Place the saucepan over medium-high heat and bring to a boil. Then turn the heat down to low and simmer for 5 minutes, whisking continuously.
Remove the sauce from the heat, it will thicken as it cools.
Cheesecake Filling
Using a hand mixer, beat the cream cheese, sour cream, sugar, and eggs together in a large mixing bowl until smooth. Mix in the flour.
Pour 1/2 of the cheesecake mixture into the Oreo crust and spoon 1/3 of the raspberry sauce over the filling. Use a knife or skewer to swirl the sauce into the filling. Repeat with the remaining filling and 1/3 of the sauce.
Bake at 375 degrees F for 1 hour or until a toothpick comes out clean.
Remove from the oven and let cool to room temperature. Chill in the fridge for at least 5 hours to overnight.
Once the cheesecake has chilled, spread a thin layer of sour cream over the top. Then spread the rest of the raspberry sauce over the sour cream and top with fresh raspberries. Cut into 12 slices and serve.
Notes
The raspberry sauce can be made up to 1 day ahead of time. Store it in an airtight container in the fridge until ready to use.
Store any leftovers in the fridge in an airtight container.
This cheese can be frozen for up to 2 months once chilled and topped with sour cream and raspberry sauce. Thaw in the fridge overnight and top with fresh raspberries before serving.