Preheat the oven to 200 °C. Soak rolls in milk, squeeze liquid out and strain through a sieve. Mix meat and the rolls by hand. Pell onion, chop and fry golden brown in the butter. Mix meet with bacon, egg, salt, pepper, marjoram, caraway seed, the fried onion, parsley, crushed garlic and whipping cream. Shape mass to a roll on a board with breadcrumbs. Melt butter. Pour butter over the meat loaf in a casserole and roast in the oven for 55 minutes. Baste occasionally with beef stock. Remove the roast ten minutes before it is finished, coat with smoothly mixed sour cream, return to the oven until a soft crust has developed. Take the roast out of the oven, carfully lift out of the casserole and keep warm. Mix the meat juice with flour and mustard, season with some lemon juice to taste, boil briefly once.