For the puree, peel, wash and chop the potatoes, cover and cook in salt water for about 20 minutes.
For the croÛtons, dice the rolls. Heat 2 tablespoons of butter in a frying pan. Fry the bread cubes in it until golden brown. Season with salt and pepper. Remove.
For the mustard cream, peel onion and carrot and cut into very fine cubes. Heat 1 tablespoon of oil in a frying pan. Fry the diced onion and carrot for about 3 minutes. Deglaze with wine and vinegar, bring to the boil and simmer for about 5 minutes.
Stir in cream and mustard. Season to taste with salt and pepper. Keep warm.
For the steaks dab meat dry. Heat 2 tablespoons of oil in a frying pan. Fry the steaks in it in 2 portions on each side for about 3 minutes. Season with salt and pepper. Take out, wrap in aluminium foil and let it rest for about 5 minutes.
For the puree, drain the potatoes, add milk and 1 tbsp. butter and mash coarsely. Season to taste with salt and nutmeg. Arrange the steaks with the puree and mustard cream and sprinkle with the croutons.