Cook 10 pounds waxy new crop potatoes in their jackets in boiling salted water. Peel and cut into slices or dice while still hot.
Finely chop 1/2 pound onions and sprinkle on the potatoes.
Sliver a medium to large bunch celery, with the green leaves, and add. Slice a 1 quart jar of gherkins (small sweet pickles) and add. Sprinkle with 3 Tablespoons salt and 1/2 teaspoon pepper. Add 2 cups well seasoned French or Italian dressing and toss gently to mix. Mellow by setting in a cool place, but not the refrigerator, for an hour. Drain off any excess dressing.
Spread in 3 flat pans about 9 x 13 inches. Spread each pan with 1 1/3 cups mayonnaise or salad dressing. Chop together 12 hard cooked eggs and 1 bunch parsley. Sprinkle on the salad. Mark each pan in 18 squares to make 54 portions.