Cauliflower Faux tato Salad

Soak onion in water 10 minutes; drain and pat dry. In a large bowl, whisk together vinegar, lemon juice, and mustard with oil; season with salt and pepper. Stir in onion, celery stalks and leaves.
Cut 1 pound cauliflower into bite-size florets (3 cups). Steam in a pot of salted simmering water fitted with a steamer basket until tender, 7 to 8 minutes. Drain and let cool slightly; add to salad. Toss to combine, season to taste, and serve. Salad can be transferred to an airtight container and refrigerated for up to 5 days.

Ingredient :

½ cup sliced red onion

4 teaspoons red-wine vinegar

4 teaspoons fresh lemon juice

4 teaspoons grainy mustard

⅓ cup extra-virgin olive oil

Kosher salt and freshly ground pepper

½ cup finely chopped celery stalks, plus ¼ cup chopped celery leaves

1 pound cauliflower, cut into bite-size florets (3 cups)