2. Make the Filling
Combine the cream cheese, remaining 1 1/2 cups (300g) sugar, eggs, lemon zest and juice, and vanilla in a food processor or stand mixer. Process or mix until just smooth. Scrape down the sides of the bowl, then process again, stopping to scrape down the bowl again if necessary. Stop as soon as the mixture is well blended; you don't want it to become too aerated.