Grease a tart mould with a lifting base (28 cm Ø) and dust with flour. 250 g flour, 2⁄3 Nuts, 1 teaspoon each of sugar and salt, 1 egg, 125 g butter in pieces and 3-4 tbsp. cold water, first with the dough hooks of the mixer, then quickly knead into a smooth dough with your hands. Roll out to a circle (approx. 32 cm Ø) on a floured work surface. Place in the mould, press down the rim. Prick the base several times with a fork and chill for approx. 45 minutes.
Peel and chop the onions. Peel, wash and chop the carrots. Wash rosemary, dab dry, chop needles. Clean, wash and cut cabbage into fine strips from the stalk. Fry the chopped cabbage in hot oil until crumbly. Fry onions, carrots, rosemary and cabbage for about 10 minutes. Season with salt and pepper. Let cool down a little bit.
Preheat oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see manufacturer). Mix 250 g sour cream and 4 eggs, season with salt, pepper and nutmeg. Sprinkle the rest of the nuts on the base. Add chopping mix and sour cream mixture. Sprinkle with cheese. Bake in the oven on the lowest shelf for about 50 minutes. Remove the quiche and let it rest for a short time. Serve with remaining sour cream.