This recipe came from Cook's Illustrated magazine.
All-American Potato Salad
Note that this recipe calls for celery seed, not celery salt; if only celery salt is available, use the same amount but omit the addition of salt in the dressing. The recipe also recommends russet potatoes. While other kinds can be used, there's a scientific reason for using russets - they absorb flavor deep into their center. Other potatoes only absorb flavor on their exterior and make for a bland salad. Because russets are structurally weak (which makes them absorb flavor), they tend to fall apart when cooked. Therefore, do not overcook the potatoes or they will become mealy and will break apart. The potatoes must be just warm, or even fully cooled, when you add the dressing. If you find the potato salad a little dry for your liking, add up to 2 tablespoons more mayonnaise.
2 pounds (3 to 4 medium) russet potatoes, peeled and cut into 3/4-inch cubes
1 tablespoon salt
2 tablespoons white vinegar
1 celery rib, chopped fine (about 1/2 cup)
2 tablespoons minced red onion
3 tablespoons sweet pickle relish (optional, but recommended)
1/2 cup mayonnaise
3/4 teaspoon powdered mustard (prepared mustard does not have the same punch)
3/4 teaspoon celery seed
2 tablespoons minced fresh parsley
1/2 teaspoon salt
1/4 teaspoon black pepper
2 large hard-boiled eggs, peeled and cut into 1/4-inch cubes (optional)
Place the potatoes in a large saucepan and add water to cover by 1 inch. Bring to a boil over medium-high heat. Add 1 tablespoon salt. Reduce heat to medium and simmer until potatoes are tender, about 8 minutes.
Drain the potatoes and transfer to a large bowl. Add vinegar and using a rubber spoon, toss gently to combine. Let stand until potatoes are just warm - about 20 minutes.
While potatoes are cooling, in a small bowl, stir togeter celery, onion, pickle relish, mayonnaise, powdered mustard, celery seed, parsley, 1/2 teaspon salt, and pepper.
Using the rubber spatula, gently fold the dressing and eggs into potatoes.
Cover with plastic wrap and refrigerate until chilled, about 1 hour.