Soak plums in port wine and let them steep for about 1 hour. Wash the turkey breast, dab dry and rub with salt and pepper. Heat the oil in a large pan and fry the turkey roast vigorously on all sides.
Place on the fat pan of the oven. Cook in the preheated oven (electric cooker: 200 °C/ circulating air: 175 °C/ gas: level 3) for approx. 1 1/4 hours. Clean, wash and coarsely chop the greens. Wash the thyme.
Place the soup greens, juniper berries and thyme on the fat pan and fry for about 15 minutes. Then gradually add 1/2 litre of water. Heat the lard in a pot. Add red cabbage. Add cloves, bay leaf and 2 tablespoons cranberries and bring to the boil.
Simmer for 20-30 minutes. Drain plums on a sieve, collect port wine. Form 24 dumplings from the dumpling dough, press them slightly flat and put a plum in each. Form into dumplings again. Leave to stand in boiling salted water for about 15 minutes.
Take the roast out of the oven. Pour the roast through a sieve into a pot. Add port wine and poultry stock, bring to the boil and thicken with sauce thickener. Stir in 2 tablespoons of cranberries. Season to taste with salt and pepper.
Drain the dumplings. Cut the roast open. Arrange roast, red cabbage, dumplings and some sauce on plates. Garnish roast with thyme if desired. Add the rest of the sauce.