01 - Preheat oven to 340°F. Line the bottom of a 9-inch springform pan with parchment paper.
02 - Pulse graham crackers in a food processor until finely ground. Combine crumbs with melted butter, sugar, and salt. Press mixture firmly and evenly into the bottom of the prepared pan. Bake for 10 minutes, then set aside to cool while preparing the filling.
03 - In a large mixing bowl, beat Greek yogurt, cream cheese, and sugar together using an electric mixer until completely smooth and creamy, about 2-3 minutes.
04 - Add eggs one at a time, beating well after each addition until fully incorporated. Scrape down the sides of the bowl as needed.
05 - Mix in vanilla extract, lemon zest, lemon juice, cornstarch, and salt. Beat until just combined, being careful not to overmix.
06 - Pour the filling over the cooled crust. Smooth the top with an offset spatula. Bake for 50 minutes, or until the edges are set but the center still has a slight wobble when gently shaken.
07 - Turn off the oven and crack the door open slightly. Leave the cheesecake inside for 1 hour to cool gradually, preventing cracks from forming.
08 - Remove from the oven and let cool completely to room temperature. Refrigerate for at least 4 hours, preferably overnight, until fully set.
09 - Combine sour cream (or Greek yogurt), powdered sugar, and vanilla extract in a small bowl. Spread evenly over the chilled cheesecake before serving.
10 - Slice with a sharp knife dipped in hot water, wiping the blade clean between cuts for neat, professional slices.