Sernik

Press twarog through a fine sieve twice for smoothness. Cream butter with sugar until fluffy.

Beat egg yolks into the butter mixture one at a time. Add vanilla and lemon zest.

Fold in the sieved twarog and flour until smooth.

Whip egg whites with salt to stiff peaks. Gently fold into the cheese mixture.

Pour into a buttered and floured springform pan. Bake at 170C (340F) for 1 hour until set and golden.

Turn off oven, crack door open, and let cheesecake cool gradually. Dust with powdered sugar before serving.