To start, make the raspberry filling. Add the cornstarch, lemon juice, and warm water to a small bowl and whisk together until the cornstarch has dissolved.

Combine the raspberries and sugar together in a medium to large saucepan and heat over medium heat, stirring continuously for 3 minutes as the juices release.

Add the cornstarch mixture and continue cooking for another 3 minutes, smashing the raspberries as they cook. The mixture should bubble a little bit and just start to thicken.

Puree the raspberry mixture in a food processor and then strain the puree. Set puree aside to cool.

Preheat oven to 325°F (163°C). Line a 9-inch (23cm) springform pan with parchment paper in the bottom and grease the sides.

Combine the crust ingredients in a small bowl. Press the mixture into the bottom and up the sides of the springform pan.

Bake the crust for 10 minutes, then set aside to cool.

Cover the outsides of the pan with aluminum foil so that water from the water bath cannot get in. Set prepared pan aside.

Reduce oven temperature to 300°F (148°C).

In a large bowl, beat the cream cheese, sugar and flour on low speed until well completely combined and smooth. Be sure to use low speed to reduce the amount of air added to the batter, which can cause cracks. Scrape down the sides of the bowl.

Add the sour cream, lemon juice and lemon zest and mix on low speed until well combined.

Add the eggs one at a time, mixing slowly to combine after each addition, then add the egg yolks and mix until combined. Scrape down the sides of the bowl as needed to make sure everything is well combined.

Add two tablespoons of the cheesecake filling to the cooled raspberry filling.

Fill the crust with about ¾ of the cheesecake filling.

Drop spoonfuls of about ½ of the raspberry filling onto the cheesecake filling. Use a knife or spatula to run through the spoonfuls and swirl them around.

Drop spoonfuls of the remaining filling over the raspberry swirl and gently spread evenly. Then drop spoonfuls of the remaining raspberry filling over the top of the cheesecake and use a knife or spatula to swirl it around.

Place the springform pan inside another larger pan. Fill the outside pan with enough warm water to go about halfway up the sides of the springform pan. The water should not go above the top edge of the aluminum foil on the springform pan.

Bake for 1 hour 25 minutes. The center should be set, but still jiggly.

Turn off the oven and leave the door closed for 30 minutes. The cheesecake will continue to cook, but slowly begin to cool as well.

Crack the door of the oven for 30 minutes to allow the cheesecake to continue to cool slowly. This process helps prevent cracking.

Remove the cheesecake from the oven and water bath wrapping and place the cheesecake in the refrigerator to cool completely.

Remove the cheesecake from the springform pan and place on a serving dish.

Top the cheesecake with raspberries and lemon slices, then refrigerate the cheesecake until ready to serve. Cheesecake is best if eaten within 3-4 days.