Sour Cream Potato Salad

8 med. potatoes, boiled

1 8 oz. carton sour cream

2 sm. onions, finely chopped

1 c. fresh parsley, finely chopped

½ tsp. salt

2 tsp. prepared horseradish

1 ½ c. mayonnaise

Alternate layers of sliced potatoes and the sauce mixture in a 2-quart oblong Pyrex dish. Flavors are better if made the day before.