Steam Cauliflower: Place a steamer basket in a large pot, then add enough water to cover the bottom, not rising above the basket. Add the chopped cauliflower to the basket. Bring to a boil, then reduce heat to medium. Cover and steam for 5-7 min, until just fork-tender. Carefully remove the cauliflower. Set aside to cool.
Make the Dressing: To a large bowl, add the vegan mayo (see notes for oil-free tofu mayo option), Dijon, dill pickle juice, garlic powder and smoked paprika. Season with salt and pepper, then whisk to combine.
Toss Salad: When the cauliflower is cool to the touch, add to the bowl with the dressing. Season cauliflower with salt and pepper. Add the celery, chives, red onion, pickle and dill. Season with more salt and pepper to taste, if needed.
Chill: Refrigerate for at least an hour or until ready to serve.
Serve: Garnish the “potato” salad with extra chives and a sprinkle of smoked paprika, if desired.