Preheat your oven to 350°F (175°C). In a mixing bowl, combine graham cracker crumbs and melted unsalted butter. Press into the bottom of a greased springform pan. Bake for 10 minutes, then let cool.

In a saucepan over medium heat, combine fresh strawberries and sugar. Cook until softened, about 5-7 minutes. Puree until smooth and set aside to cool.

In a large mixing bowl, beat cream cheese until creamy. Gradually add sugar, then add eggs one at a time, mixing well. Fold in sour cream and vanilla until smooth.

Pour half of the cheesecake filling onto the crust. Drop spoonfuls of strawberry sauce, then add remaining filling. Swirl the sauce gently.

Prepare a water bath. Place the cheesecake in the oven and bake for 60-70 minutes until the edges are set but the center jiggles.

Turn off the oven and leave the cheesecake with the door ajar for 1 hour. Remove and let cool completely on a wire rack, then refrigerate for at least 6 hours before serving.