3 eggs, beaten
3/4 c. vinegar
1 tsp. mustard
1 tsp. salt
2 tsp. flour
1/4 tsp. pepper
1/2 c. sugar

Cook slowly until thick. Mix Half & Half (just enough to thin to the right consistency for coating the potatoes) with mayonnaise.

This is the only dressing for potato salad I use. Don't know how many times I called Grandma to get the recipe, I was always misplacing it.