Preheat the oven (electric cooker: 100°C/circulating air and gas, see manufacturer). Wash fillets, dab dry and cut both lengthwise, but do not cut through. Wash the rosemary, dab dry and chop the needles coarsely.
Mix plums, apricots and half rosemary. Spread into the incisions. Tie the fillets with kitchen string like a parcel. Put them in a flat roaster and roast them in the oven for about 2 hours.
Clean, wash and quarter the savoy cabbage. Cut cabbage into strips from the stalk. Peel and chop the onion. Heat the lard in a pot. Sauté onion and savoy cabbage in it. Season with salt and pepper. Add 150 ml water, cover and stew for about 30 minutes.
Add cream and braise for about 10 minutes.
Cut the bacon into strips. Fry in a pan without fat until crispy. Fry the rest of the rosemary briefly. Take out. Take the fillets out of the oven and fry them in bacon fat for 6-8 minutes. Let the bacon mix and fillets, wrapped in foil, rest briefly.
Add cognac and 100 ml water to the roast, simmer for 2-3 minutes. Stir starch and 2 tbsp. water until smooth. Stir into the boiling sauce, simmer for about 2 minutes. Season to taste with salt and pepper. Arrange everything.
Potatoes taste good with it.