Knead flour, 1 egg, 1/2 teaspoon salt, butter in pieces and 1-2 tablespoons water first with the dough hooks of the hand mixer, then with your hands to a smooth dough. Cover and chill for about 30 minutes.
In the meantime, clean and wash the cauliflower and cut it into large pieces. Bring a pot of salted water to a boil over medium heat and cook the cauliflower for about 7 minutes until al dente and then quench.
Clean the leek, cut into coarse rings and wash well. Cut the smoked pork loin into large cubes. Heat oil in a pan. Sauté the cubes of smoked pork in it over medium heat, briefly sauté the leek rings.
Mix 4 eggs with sour cream, season with salt and pepper. Grease a tart tin (bottom 22 cm; top 26 cm Ø; 4 cm height). Roll out the dough on a floured work surface (approx. 30 cm Ø).
Lay out the mould with it, press the edge. Cut off excess edge. Spread the cauliflower, cured pork loin and leek in the tart mould and pour the sour cream egg glaze over it. Crumble the rolls into breadcrumbs and sprinkle over them.
Sprinkle with grated Emmental cheese. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 50 minutes. Remove the tart, lift it out of the tin and cut into 8 pieces.
Arrange on plates.