Bring the milk, sugar, vanillin sugar and lemon zest to the boil. Stir in semolina and simmer at low heat for about 5 minutes.
Separate the egg. Stir the egg yolk into the hot semolina. Beat egg white and 1 pinch of salt until stiff. Fold in the egg white. Spread everything in a greased flat form (approx. 20 x 20 cm). Let it cool down.
Heat the cream. Roughly dice the nougat and melt in it. Loosen the semolina mixture at the edge, turn it over and cut it into rhombs.
Heat butter in a frying pan. Fry semolina slices in it in portions until golden brown. Serve with nougat sauce and sprinkle with pistachios.