For the meatloaf, soak the roll in cold water. Preheat the oven (electric cooker: 180 °C/circulating air: 160 °C/gas: see manufacturer). Peel 2 onions and chop finely. Squeeze the roll well. Knead minced meat, roll, onions, eggs and ketchup. Season with 2 tsp. salt and Tabasco. Shape into an oblong roast and place on a baking tray. Bake in a hot oven for about 1 hour.
Meanwhile peel 500 g onions and cut them into rings. Heat the oil in a pot. Fry the onions in it. Sprinkle with 2 tablespoons of sugar and caramelize lightly. Dust with flour and sauté briefly. Deglaze with wine while stirring. Bring to the boil, season with salt and pepper and simmer for about 30 minutes at low heat. Stir from time to time.
Peel and wash the carrots and potatoes and cut them into pieces. Cover and cook in salted water for about 20 minutes. Drain, let it evaporate briefly. Add butter and milk and mash everything to a coarse puree. Season to taste with salt and nutmeg. Cut the roast open and serve with onion sauce and puree.
The meat loaf is generously calculated - in case someone is particularly hungry. What's left over can be sliced and fried in a pan or eaten cold with mustard on bread.