Potato salad pie recipe from 1963

3 pounds potatoes

2 cups diced celery

1/4 cup finely chopped onion 

1/4 cup finely chopped parsley

1 cup mayo

2 tsp. cider vinegar

2 tsp. salt

1/4 tsp. pepper

mayo, tomatoes, watercress to garnish

Cook potatoes until tenderș peel and chill. Slice thinly or dice. Add celery, onion, parsley, 1 cup mayo, vinegar,s easoning. Toss lightly until well mixed. Press into 9 inch pie plate. Build edges as for pastryȘ smooth center. Chill at least 3 hours. Before serving, cover center generously with mayoș decorate with tomatoes and watercress.