Dab meat dry. Season with salt and pepper. Place the meat on the fat pan of the oven. Roast in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 1 1/4 hours.
Peel the carrot and 1 onion, chop coarsely and add to the roast. Gradually add 3/4 litres of warm water. Cut the honey cake into cubes, add half to the meat about 30 minutes before the end of the frying time.
Clean and wash the Brussels sprouts. Form 18 dumplings from the dumpling dough, put them into boiling salted water and let them simmer at low heat for 15-20 minutes. Peel and finely dice 1 onion. Melt butter in a pot.
Brown the Brussels sprouts and onion in it, season with salt and nutmeg. Pour on 1/8 litre of water, bring to the boil and stew for about 15 minutes. Take the meat out and keep warm. Pour roast in a sieve, fill up to 1/2 litre with water and bring to the boil.
Stir in the rest of the honey cake, season with salt and pepper. Arrange roast, Brussels sprouts and dumplings on a plate. Garnish with star anise. Serve with extra sauce.