Ingredients for 4 servings: 600 g veal or beef liver, 3 large onions, 3 tbsp flour, 3 tbsp clarified butter or oil, salt and pepper. For the sauce: 150 ml beef stock, 1 tsp mustard, 1 tsp butter, and a splash of apple cider vinegar, if desired. For the mashed potatoes: 900 g floury potatoes, 200 ml milk, 40 g butter, salt, and nutmeg.
Peel the potatoes, cut them into small pieces, and boil them in salted water for about 20 minutes until tender. Meanwhile, slice the onions into thin