Preheat oven to 350F and line a 8x8 inch baking pan with parchment paper and set to the side. Combine graham cracker crumbs, sugar, and melted butter together in a small bowl and stir. Press into the baking pan to create the crust and bake for 8 minutes. While crust is cooling, beat together cream cheese, lemon zest, sugar, sour cream, flour, and vanilla extract.