In a food processor or large bowl, mix together the flour, granulated sugar, and salt. Incorporate the cold butter cubes.
In a large bowl, beat softened cream cheese with sugar until smooth. Add the flour, powdered sugar, lemon juice, eggs, and vanilla. Mix just until everything is incorporated.
Pour the filling evenly over the warm crust. Return the pan to the oven and bake for 30 minutes, or until the filling is set.