Preheat the oven to 350°F (175°C). Lightly grease a small springform pan or pie dish.
In a bowl, combine the graham cracker crumbs, crushed walnuts, melted butter, and sugar. Mix until evenly moistened. Press firmly into the bottom of the pan to form the crust. Set aside.
In a large bowl, beat the cream cheese until smooth. Add the shredded Parmesan and sugar, mixing until well incorporated.
Add the egg yolks one at a time, stirring gently after each addition. Mix in the lemon juice and lemon zest until smooth.
In a separate bowl, lightly whip the egg whites until they hold soft peaks. Do not overwhip.
Gently fold the egg whites into the cheesecake batter, taking care not to deflate them. This will give the cheesecake a lighter texture.
Pour the filling over the prepared crust and smooth the top.
Bake for 35–40 minutes, or until the center is just set and the top is lightly golden.
Allow the cheesecake to cool completely before slicing. Chill for at least 1 hour for best texture.