01 - Preheat the oven to 325°F. Grease a 9-inch springform pan with butter and line the base with parchment paper, ensuring the paper sits flat against the bottom.
02 - In a mixing bowl, combine the graham cracker crumbs, melted butter, and sugar until the mixture resembles wet sand. Press firmly and evenly into the bottom of the prepared pan. Bake for 10 minutes, then remove and set aside to cool slightly.
03 - Using an electric mixer, beat the cream cheese on medium speed until completely smooth and free of lumps. Add the sugar and continue beating until fully incorporated. Add the eggs one at a time, mixing thoroughly after each addition. Blend in the sour cream, vanilla extract, flour, and salt until just combined — avoid overmixing to prevent cracks.
04 - Pour the filling over the partially cooled crust. Gently tap the pan on the counter several times to release trapped air bubbles. Bake on the center rack for 50 to 60 minutes, until the edges are set but the center still has a slight jiggle when gently shaken.
05 - Turn off the oven, crack the door open slightly, and let the cheesecake rest inside for 1 hour. This slow cooling process prevents the top from cracking.
06 - Transfer the cheesecake to a wire rack and cool to room temperature. Refrigerate for at least 4 hours, or preferably overnight, for the best set and texture.
07 - Whisk together the sour cream, powdered sugar, and vanilla extract until smooth. Spread evenly over the chilled cheesecake surface before serving.
08 - Dip a sharp knife in hot water and wipe dry before each cut for clean, professional slices. Serve chilled.