Creamy cucumbers and onions

Our family had two versions of this cucumber and onion salad.  One had a dressing of vinegar, water, sugar and dill.  This version is the creamy version. The dressing for this one uses sour cream which gives it a special creamy dressing.  Soooo, good.  You can add dill to this one if you want.  The longer it sets for the flavors to blend the better.  You can enjoy it over several days and it just keeps getting better.