01 - Preheat oven to 325°F (160°C). Line the bottom of a 9-inch springform pan with parchment paper, ensuring a snug fit.
02 - Combine graham cracker crumbs, melted butter, and granulated sugar in a bowl until evenly moistened. Press the mixture firmly into the bottom of the prepared pan, creating an even layer. Bake for 10 minutes, then set aside to cool.
03 - In a large mixing bowl, beat the softened cream cheese with an electric mixer until completely smooth and free of lumps. Gradually blend in the granulated sugar, mixing until fully incorporated.
04 - Add the eggs one at a time, beating well after each addition. Blend in the sour cream, vanilla extract, all-purpose flour, and lemon juice. Mix until just combined—avoid overmixing to prevent air bubbles.
05 - Pour the filling over the cooled crust and smooth the surface with a spatula. Bake for 45 minutes, or until the edges are set but the center still has a slight jiggle.
06 - Turn off the oven, crack the door open, and allow the cheesecake to rest inside for 1 hour. This gentle cooling prevents cracks from forming on the surface.
07 - Transfer the cheesecake to a wire rack and let it cool to room temperature. Refrigerate for at least 4 hours, preferably overnight, for the best texture and clean slicing.
08 - For the sour cream topping, whisk together sour cream, powdered sugar, and vanilla extract until smooth. Spread evenly over the chilled cheesecake just before serving.