Preheat oven to 350 degrees F.

In a large bowl mix the graham cracker crumbs, butter, granulated sugar, and salt together evenly. Press the mixture into the bottom and up the sides of 9-inch springform pan evenly.

Bake the crust for 8-10 minutes, or until lightly golden. Set aside and let cool while you make the sauce and cheesecake filling.

In a small sauce pan, heat strawberry jam over medium heat with ½ cup water. stir occasionally for 5-7 minutes until the jam is liquid and mixed with the water.

Mix some of the liquid with the cornstarch to create a slurry then mix it with the jam mixture in the pan. Stir and allow to thicken for another 3 minutes. Pour into a bowl, cover, and cool in the fridge.

Preheat oven to 325 degrees F.

In the bowl of your stand mixer fitted with the paddle attachment, beat the cream cheese well on medium speed for a minute to ensure there will be no lumps. Add sugar, cornstarch, and salt and beat on medium speed, until smooth, scraping the sides of the bowl with a rubber spatula as necessary to make sure all the sugar and cream cheese are mixed.

Turn the mixer to low/stir and add the sour cream, lemon zest, and vanilla; mix well, scraping sides of the bowl as needed. Add the eggs, one at a time, mixing on low speed after each addition just until mixed. Don’t over mix, your cheesecake will crack. 

Pour half the filling over the crust evenly, then spoon in and swirl a generous amount of ½ teaspoon dollops of the strawberry sauce in the filling. Pour the rest of the cheesecake filling over the first layer, then repeat dolloping and swirling with more strawberry sauce until satisfied with the amount of swirls.

Double wrap the bottom edges of the springform pan with foil, sealing tightly to prevent water from getting into the pan and making your crust soggy.

Place the springform pan into a larger oven-safe pan and pour very hot water into the large pan, until it’s ¾-1 inch deep, making sure the water doesn’t come up higher than the foil.

Bake for 55-65 minutes or until the center is almost set. The center will still jiggle while the edges will be set and puffed up slightly. If you see any cracking while checking at the 55 minute mark, immediately proceed to the cooling step 

Allow the cheesecake to cool in the oven with the door open for at least an hour, then cover with plastic wrap and transfer into the refrigerator to set up for at least 6 hours.

Release the sides of the springform pan before pouring the residual strawberry sauce over the top if desired (or serve on the side). Slice and serve.