Cook potatoes in salted water. Mushrooms, onions and parsley finely. In a pan, melt the butter and sauté the onion him and mushrooms - about 5 minutes, seasoned with lemon juice. Downloaded smash potatoes and season with salt and pepper. They add the flour, egg and cream. From the resulting potato mixture form meatballs, which are fried in a pan until golden. On finished meatballs put the mixture with mushrooms and onions and sprinkle with parsley.