Dab roast beef dry and remove the fat edge, up to 1⁄2 cm. Season meat with salt and pepper. Heat 2 tablespoons of oil in a flat roasting pan. Fry the meat in the pan for about 8 minutes.
Roast in a hot oven (electric cooker: 80 °C/circulating air and gas: see manufacturer) for approx. 4 1⁄2 hours.
Wash the tomatoes. Heat 1 tablespoon of oil in a frying pan. Fry the tomatoes for about 5 minutes. Season with salt and pepper, remove and put aside. Caramelize sugar in the hot frying fat until golden brown.
Pour in vinegar, bring to the boil and boil down for about 2 minutes until creamy.
Remove the roast beef and leave it to rest for at least 30 minutes (preferably overnight) so that it does not lose so much juice when sliced.
Finely slice the parmesan. Cut mozzarella into thin slices. Clean, wash and shake dry the arugula. Wash basil, shake dry and pluck the leaves from the stalks. Cut roast beef into thin slices and arrange on a large plate.
Spread tomatoes, whole cheese, arugula and basil on top. Drizzle with olive oil and balsamic cream.