Spiralize the zucchini and place it in a large bowl.
In a small container or bowl combine the olive oil, sherry vinegar, white wine vinegar, scallions, Dijon mustard, salt and pepper. Stir or shake to blend well. Drizzle the dressing over the zucchini noodles and toss to coat well.
Refrigerate for at least 30 minutes, and up to a day, for the vinaigrette to soak into and soften the zoodles slightly. Don’t you like a salad that you not only can but should dress ahead?
Notes
You could definitely throw in a handful of chopped fresh herbs. You could throw in halved cherry or grape tomatoes for color. You could mix up summer squash and zucchini for a cool color mix.