Begin by covering your potatoes in a pot with water. The water should be about an inch above the top of the potatoes.

Place on stove and bring to a boil and cook potatoes until fork tender. The potatoes should be cooked through but still firm. The timing will depend on the size of your potatoes, but it should take about 15-20 minutes.

Drain potatoes and let cool.

While potatoes are cooking, boil eggs. To hard boil, place eggs in a pot with water and place on stove. Bring to a boil and once boiling cover and immediately turn off heat. Wait 15 minutes and then place in an ice bath and peel. 

Cut up potatoes and place in a large bowl. Add peeled and sliced eggs, diced celery, onions, peas, mayonnaise, vinegar, and mustard.

Stir until well coated.

Taste and add salt and pepper to your preference.