Step 1: Preheat your oven to 325°F (160°C). Wrap the bottom and sides of a 9-inch springform pan with heavy-duty aluminum foil, ensuring it's sealed to prevent water from entering during the water bath.
Step 2: For the crust, combine graham cracker crumbs, ¼ cup sugar, and melted butter in a medium bowl. Press the mixture firmly into the bottom of the prepared springform pan. Bake for 10 minutes, then remove from oven and let cool slightly.
Step 3: In the bowl of a stand mixer fitted with the paddle attachment, or with a hand mixer, beat the softened cream cheese on medium-low speed until smooth and creamy, about 2-3 minutes. Scrape down the sides of the bowl.
Step 4: Gradually add 1½ cups sugar, then the flour, vanilla extract, and salt, mixing on low speed until just combined. Do not overmix.
Step 5: Stir in the sour cream until fully incorporated. One at a time, add the eggs, mixing on low speed after each addition just until the yolk disappears. Be careful not to incorporate too much air.
Step 6: Pour the cheesecake batter over the cooled crust in the springform pan. Place the springform pan inside a larger roasting pan. Carefully pour hot water into the roasting pan until it reaches halfway up the sides of the springform pan.
Step 7: Carefully transfer the roasting pan to the preheated oven. Bake for 1 hour 15 minutes to 1 hour 30 minutes, or until the edges are set but the center still jiggles slightly when gently shaken. The internal temperature should be 150°F (65°C).
Step 8: Turn off the oven, crack the oven door open slightly (you can use a wooden spoon), and let the cheesecake cool in the oven for 1 hour. This slow cooling helps prevent cracks.
Step 9: Remove the cheesecake from the water bath and the roasting pan. Carefully remove the foil from around the springform pan. Let it cool completely on a wire rack at room temperature. Once cooled, cover loosely with plastic wrap and refrigerate for at least 6-8 hours, or preferably overnight, before serving.
Step 10: To serve, run a thin knife around the edge of the pan before releasing the springform. Slice with a hot, clean knife for perfect cuts.