Peel and dice onion with other soup vegetables. Melt margarine in a saucepan and fry vegetables about 5 minutes. Add broth, bay leaf, salt and pepper to taste. Add peeled potatoes in the soup, heat to a boil and cook on low heat until become soft. Dice sausages. Fry sliced bacon on a dry pan, roast diced sausages in a melted fat. Add bacon and sausages in the soup,stir, serving with sour cream.