Preheat oven to 350°F / 175°C. Line the bottom and the sides of a 9" (23cm) springform pan with parchment paper. Watch the photo-tutorial in the blog post above on how to line a springform pan properly. Set aside.
Graham cracker crust: In a large bowl combine all ingredients and stir until evenly moistened. Transfer to the prepared pan and press crust with the back of a flat-bottomed cup into the bottom and halfway up the sides. Bake for 10 minutes. Remove from oven and allow to cool until you are done with the filling.
Lemon cheesecake filling: In a large mixing bowl, using a handheld or stand mixer fitted with a whisk attachment, whisk the cream cheese, sugar, and flour just until combined no lumps remain. Add sour cream, lemon juice, lemon zest, and vanilla* and stir to combine. Add one egg at the time and mix just until combined before you add the next egg. Scrape down the bowl before you add the last egg. Mix to combine. Don't overmix at any step. Too much air in the filling can cause cracks while baking.
Pour filling into the prebaked crust and spread evenly. Place a piece of parchment paper under the springform pan and bake for 45-55 minutes until the edges are set. The center should be very bright and almost set with a 3-4 inches wobbly spot in the center. Don't overbake until the cheesecake is browned because this is a common reason for cracked cheesecake. The cheesecake will firm up as it cools. I baked mine for exactly 45 minutes. Watch photo above (how to tell when a cheesecake is done) to see how the baked cheesecake should look like.
Turn off the oven, crack open the door (pinch a wooden spoon), and let the cheesecake in the oven for another hour. Then remove from the oven and let cool to room temperature. Refrigerate at least 4 hours or overnight. Decorate before serving, if desired. You find additional recipes for toppings in the blog post. Store leftovers in an airtight container in the fridge up to 3 days.