1. Cover the duck legs with the duck fat and simmer in the oven at 80 °C for 6.5 hours.
2. Boil the potatoes for 25 minutes, peel and mash until smooth.
3. Cool the potatoes and add salt. Then add the flour and a whisked egg. Knead the dough and form into rolls.
4. Remove all the bones from the duck legs, season with cumin, salt and pepper, and keep the confit warm.
5. Put the dumpling rolls in water, bring to the boil and cook for 15 minutes at medium heat.
6. Simmer the fresh red cabbage juice for 10 minutes. Spoon off the foam, add vinaigrette, sugar and salt, and simmer for another 10 minutes.
7. Put the slightly cooled liquid with the xanthan into a mixer, and foam it.
8. Bake the confit for eight minutes at 200 °C.
Put a large spoonful of sauce onto each plate. Place a dumpling roll and a duck confit on the sauce, parallel to each other. Add three generous dollops of red cabbage foam.