Clean, wash and cut the carrots into large pieces. Wash and quarter the tomatoes. Peel and quarter onions. Wash the meat and pat dry. Heat oil in a roasting pan. Brown the meat all around, season with salt and pepper.
Add the onions, tomatoes and carrots to the roast, fry briefly. Cover the meat and cook in the preheated oven (electric cooker: 100 °C/ convection oven: 75 °C/ gas: unsuitable) for approx. 4 hours. In the meantime clean the carrots and leave them to stand for a while.
Put carrots in boiling salted water and cook for 10-12 minutes. In the meantime, remove meat from the roaster and keep warm. Pour gravy through a sieve, collect in a pot, drain vegetables well.
Bring the frying pan to the boil and simmer at low heat for about 6 minutes. Wash basil, shake dry, put some leaves aside for decoration. Cut remaining leaves into coarse strips.
For the sauce, stir the sauce powder into 125 ml cold water and cream. Bring to the boil briefly while stirring. Remove from the heat and fold in butter in flakes. Stir in basil strips. Cut the meat open.
Lift the carrots out of the water, drain well. Arrange meat, carrots and some basil sauce on a plate. Garnish with basil. Add the rest of the sauce and frying set. Boiled potatoes taste good with it.