Grandma Alice's Nippy Potato Salad

The sour cream and mayonnaise base add a nice tang to my Grandma's potato salad.

2 pounds red potatoes about 7-8 cups once cut up
2 Tbs red wine vinegar or in a pinch I’ve used dill pickle juice
1/2 tsp salt, more or less
1/2 tsp pepper, more or less
2 Tbs Dijon mustard
1/2 cup sour cream
1/2 cup mayonnaise
1 cup diced celery
1 dill pickle, diced about 1/2 cup, sometimes I do more
2-3 scallions, sliced thinly AND/OR 1/4 –1/2 cup diced red onion or yellow...
1/4 cup minced fresh parsley
paprika to sprinkle on top
Optional: diced pimentos, chopped black olives, sweet pickles instead of dill, diced hard boiled eggs up to 3

Cook whole red potatoes in boiling water until you can easily poke through them with a paring knife (but not to the point that they are falling apart). Large-ish potatoes (so that it took 7 to make the 2 pounds) took about 25 minutes. Adjust up or down depending on the size of your potatoes.
Drain the potatoes, rinse in cold water, drain again and let cool a bit. Cut into 1/2-3/4” inch chunks. I like skin on but you can take the skin off before cutting if you don’t like the skin. Toss the still warm potatoes with the vinegar, salt and pepper.
In a small bowl blend the mustard, sour cream and mayonnaise until smooth.
Add the celery, pickles and onions and/or scallions to the potatoes. Stir in the dressing and mix thoroughly. Sprinkle the parsley on top and mix in a bit. Chill an hour or overnight, covered. Sprinkle with paprika just before serving.