German Potato Salad

1 can (10.5 oz) condensed chicken broth
1/2 cup finely chopped onion
1/3 cups vinegar
3 tbsp olive oil
1 tbsp lemon juice
1 tsp Dijon mustard
1/4 tsp salt
1/8 tsp pepper
5 cups cubed potatoes, cooked (about 2.5 pounds)
1 cup sour cream
2 tbsp chopped parsley
grilled Knackwurst sausage

In skillet, combine chicken broth, onions, vinegar, oil, lemon juice, mustard, salt, and pepper. Bring to a boil and reduce heat. Simmer 25 minutes or until done. Let stand 30 minutes. Add potatoes. In bowl, blend sour cream and parsley. Toss well with potato mixture. Serve with grilled sausage.