Peel, wash and halve the potatoes and cook in boiling salted water for about 20 minutes. Peel shallots and cut them in half or quarters depending on size. Heat 1 tablespoon of oil and sauté the shallots for about 3 minutes. Season with salt and pepper. Deglaze with red wine and vinegar, bring to the boil and simmer for about 10 minutes
Wash liver, dab dry, season with salt and pepper and turn in flour. Heat 2 tablespoons of oil in a frying pan and fry the liver in portions for about 5 minutes each. Wash the marjoram, shake dry and, except for a little garnish, strip the leaves from the stalks.
Wash the apple, cut the fruit flesh into slices from the core and dice. Heat 1 tbsp. butter and sauté the apple cubes for approx. 4 minutes. Take out, boil milk and 50 g butter in it
Drain the potatoes, add the milk mixture and horseradish and mash with a potato masher until mashed. Season to taste with salt and fold in the apple cubes. Arrange liver, mashed potatoes and shallots. Sprinkle with marjoram and garnish