The original recipe also calls for 1/2 cup each of thinly sliced radishes, cucumber and green bell pepper, and one tomato, cut into wedges. I do not add these ingredients because I felt it made the salad too watery, however, you can add them if you wish!
Prepare and cook potatoes; cool slightly and cut into cubes (about 6 cups)
Mix mayonnaise, vinegar, mustard, salt and pepper in a large bowl.
Add potatoes, celery and onion; toss to coat.
Stir in eggs (and radishes, cucumber and bell pepper if you use them).
Cover and refrigerate at least 4 hours before serving. Garnish with tomato wedges.