Instructions:
- Preheat oven to 350°F (175°C). Wrap the exterior base and sides of a 9-inch springform pan tightly in 2-3 layers of heavy-duty foil to waterproof it.
- For the crust, combine graham cracker crumbs, ¼ cup sugar, and melted butter until evenly moistened. Press mixture firmly and evenly into the base of the prepared springform pan.
- Pre-bake the crust for 8-10 minutes. Remove and let cool slightly. Lower the oven temperature to 325°F (160°C).
- For the filling, beat the room-temperature cream cheese on medium speed until completely smooth (about 3 minutes), scraping down the sides frequently. Ensure there are absolutely no lumps.
- Gradually beat in the 1 ¼ cups of sugar and the flour until just combined.
- Mix in the heavy cream, vanilla extract, and lemon zest until incorporated.
- Add the eggs one at a time, mixing only until the yolk just disappears after each addition. Do not overmix after the eggs are added, as this incorporates air.
- Pour the filling over the cooled crust. Gently tap the pan on the counter a couple of times to release any large air bubbles.
- Set up the water bath (bain-marie): Place the foil-wrapped springform pan inside a large roasting pan. Carefully pour boiling water into the roasting pan until it reaches about halfway up the sides of the springform pan.
- Carefully transfer the setup to the oven and bake at 325°F (160°C) for 60 to 75 minutes. The edges should be set, but the center 2-3 inches should still have a slight jiggle.
- Turn off the oven, prop the door open slightly using a wooden spoon, and leave the cheesecake inside the water bath for 1 hour to allow for a slow cool-down.
- Remove the pan from the water bath, remove the foil, and let it cool completely on a wire rack at room temperature (1-2 hours).
- Cover loosely with plastic wrap and refrigerate for a minimum of 8 hours, preferably overnight, before serving. Run a thin knife around the edge before releasing the springform side.