For the crust
Spray the inside of a 9 inch springform pan with cooking spray. Crush the graham crackers in a food processor or put them in a bag and roll over them with a rolling pin until they are in crumbs. Mix the sugar and melted butter in with the crumbs. Put the graham cracker crumbs into your pan and press around the pan up the sides. Set the pan on a cookie sheet and put it aside until the filling is ready.
For the filling
Preheat the oven to 500F.
Use a mixer to stir together the cream cheese, sugar and flour until it is very smooth. You'll likely need to scrape down the mixer bowl a few times.
Add the eggs, one at a time, mixing each one in completely before adding the next. Stir in the lemon zest and vanilla extract.
Pour the filling into the pan on top of the graham cracker crust, spreading it flat with a spatula.
Put the cookie sheet with the springform pan on it into the oven on the middle rack. After ten minutes, turn the heat down to 200F without opening the door. Cook for another hour and ten minutes. Take the cheesecake out of the oven and put it on a wire cooling rack.
Run a butter knife around the sides of the pan so it doesn't pull away and crack as it cools. Let it cool completely, then cover with plastic wrap and refrigerate at least 6 hours before serving.