Place your firm potatoes in a large pot and cover them with cold water. Bring to a boil, then reduce to a simmer for about 15 minutes until fork-tender.

In a medium bowl, combine vegetable broth, apple cider vinegar, Dijon mustard, sugar, salt, and pepper. Whisk until smooth.

Cut cooled potatoes into bite-sized pieces. Combine chopped onion and celery with potatoes.

Pour the dressing over the potato mixture and toss gently to coat.

Stir in freshly chopped parsley for added flavor.

Let the salad sit for at least 10 minutes to allow flavors to meld.

Serve warm or chilled, garnished with extra parsley if desired.