Thinly slice a medium size red or white onion, separate into rings. Slice cucumbers and radishes thin using about equal amounts of each.

Place all vegetables in bowl; cover with dressing and chill.

SOUR CREAM DRESSING:

1 c. (1/2 pt.) dairy sour cream
1 tbsp. lemon juice
A pinch of powdered mustard
Salt and freshly ground pepper to taste

1 cup dressing for each 4 persons.