01 -
Combine the raspberries, sugar, cornstarch, and lemon juice in a small saucepan over medium heat. Stir and mash the mixture until it starts to thicken, about 5 minutes. Strain through a fine mesh sieve to remove seeds. Allow to cool completely.
02 -
Preheat the oven to 350°F. Line an 8x8 inch baking pan with parchment paper, leaving an overhang on the sides for easy removal later.
03 -
Combine the graham cracker crumbs, sugar, and melted butter until crumbly and moist. Press the mixture firmly into the prepared pan. Bake for 8-10 minutes, then set aside to cool. Reduce the oven temperature to 325°F.
04 -
In a large bowl, beat the cream cheese and sugar with an electric mixer on medium speed until smooth and creamy. Turn the mixer to low and blend in the eggs, egg yolk, sour cream, vanilla extract, and flour one by one until fully combined and smooth.
05 -
Pour the cheesecake filling into the cooled crust. Add spoonfuls of the cooled raspberry sauce on top of the filling. Use a knife to gently swirl the sauce into the filling, creating a marbled effect.
06 -
Bake for 30-35 minutes or until the cheesecake appears set on top and only slightly jiggly in the center. Turn the oven off, open the door a few inches, and leave the cheesecake to cool for 1 hour. Then, place on a wire rack and cool to room temperature before covering and chilling for at least 3 hours or overnight.
07 -
Use the parchment paper overhang to lift the cheesecake out of the pan. Slice into 16 squares and serve.