white potatoes (any waxy potato)
red wine vinegar
extra virgin olive oil (Nana may have used corn oil)
Directions:Boil the amount of potatoes you want to use and cook until easily pierced with a fork. Take off the stove, drain and fill the pot with cold water several times to cool down the potatoes quickly. Drain off the water again and peel the potatoes. Cut the potatoes into cubes, not thin slices, and sprinkle each layer of potatoes with a little vinegar. Once you have filled the bowl with potatoes, add finely diced red onions and finely chopped parsley. Drizzle with extra virgin olive oil and mix, then add some mayonnaise and salt and mix thoroughly. I think 1 medium red onion would be enough for 5 pounds of potatoes, along with about 1/3 a bunch of parsley. If you can do the proportions similar to those in the photo, you'll have it.