Preheat the oven to 325°F (163°C). Grease a 9-inch springform pan and line the bottom with parchment paper.
In a medium bowl, combine the graham cracker crumbs, sugar, and melted butter. Press the mixture firmly into the bottom of the prepared pan to form the crust. Bake for 10 minutes, then remove from the oven and let cool while you prepare the filling.
In a large mixing bowl, beat the softened cream cheese until smooth, about 2 minutes. Add sugar and vanilla extract, and continue to beat until creamy and well combined.
Add eggs one at a time, mixing on low speed after each addition. Scrape down the sides of the bowl as needed.
Stir in sour cream, heavy cream, and flour (if using) until smooth and combined.
Pour the cheesecake filling into the cooled crust and smooth the top.
Bake for 1 hour 10-15 minutes, or until the edges are set but the center is slightly jiggly.
Turn off the oven, crack the oven door slightly, and let the cheesecake cool in the oven for 1 hour.
After an hour, remove the cheesecake from the oven and allow it to cool to room temperature. Then, refrigerate for at least 4 hours, or overnight, to set completely.
Before serving, run a knife around the edges of the cheesecake to loosen it from the pan. Release the springform pan and transfer the cheesecake to a serving platter.
Optionally, top with fresh berries, whipped cream, or your favorite fruit topping before serving.