Hesson Gardan Party Potato Salad

I grew up near a small village called Hesson, Ontario.  One of the highlights of the year was the annual St. Mary's Parish Garden Party.  On the menu was a potato salad that always got rave reviews.  This recipe from my Great-Grandmother is close to what was found at that annual event.
Cook potatos and allow to cool (do not overcook them, you don't want them to be mushy).
Dice or grate potatoes, add a chopped green onion and some chopped celery.  Can also add 2-3 chopped hard boiled eggs.

Salad Dressing
1 cup white sugar
1 tbsp flour
2 tbsp dry mustard
1 tsp salt
Mix together in a saucepan and then add:
1 tbsp butter
1 cup white vinegar
2 eggs (beaten)
Cook until thick on medium heat.

Add about 1/4 cup of the salad dressing with half & half cream.  Add to potatoes to make creamy.