Preheat the oven to 325°F (163°C).

In a medium bowl, combine the graham cracker crumbs, melted butter, and granulated sugar. Press the mixture firmly into the bottom of a 9-inch springform pan to form the crust.

Bake for 10 minutes, then remove from the oven and let cool.

In a large mixing bowl, beat the softened cream cheese with a hand mixer until smooth.

Gradually add in the granulated sugar and vanilla extract, mixing until well combined.

Add the eggs one at a time, mixing on low speed until just incorporated.

Mix in the sour cream until smooth.

In a separate bowl, combine the pureed strawberries, cocoa powder, and powdered sugar. Mix until smooth.

Pour half of the cream cheese mixture over the cooled crust.

Drop spoonfuls of the strawberry mixture over the cream cheese layer, then pour the remaining cream cheese mixture on top.

Use a knife or skewer to swirl the strawberry mixture into the cheesecake for a marbled effect.

Bake the cheesecake in the preheated oven for 55-60 minutes, or until the center is set but still slightly jiggly.

Turn off the oven and leave the cheesecake inside for an additional hour to cool gradually.

Remove from the oven and let cool to room temperature, then refrigerate for at least 4 hours or overnight before serving.