Clean or peel, wash and chop the soup greens. For the meat marinade peel and chop 1 onion. Bring vinegar, wine, 600 ml water, soup greens, onion, bay leaf, juniper and peppercorns to the boil and allow to cool.
Dab meat dry and place in a freezer bag. Pour in cooled marinade. Close the bag well. Marinate overnight in the refrigerator.
Remove meat from the marinade and pat dry. Pour the marinade through a sieve and collect the stock. Peel the rest of the onions, dice 1. Knead the mince and diced onions. Season roulades with salt and pepper.
Spread the mince on the roulades, roll up the meat and pin it with wooden skewers.
Heat the oil in a frying pan. Fry the roulades in it thoroughly all around, take them out. Fry the marinated vegetables in the frying fat. Deglaze with the marinade. Bring to the boil, add the roulades and braise covered for approx. 1 1⁄2-1 3⁄4 hours.
Dice the rest of the onions. Peel, quarter, core and dice the apple. Heat butter. Sauté onions in it. Add red cabbage and apple, bring to the boil, cover and stew at low heat for 20-30 minutes.
Finely dice the breakfast cake. Remove the roulades and keep them warm. Pour the roast stock through a sieve into a pot. Add cake, bring to the boil and simmer for about 5 minutes. Season sauce with salt and pepper.
Arrange roulades with sauce and red cabbage. Served with potato dumplings.