For the dressing: Mix all the ingredients together. Season to taste.
Using a sharp knife or a mandoline, trim the ends and stems from the fennel. Thinly slice the fennel bulb. Place the sliced fennel in a bowl, add half the dressing and toss. This can be stored in the fridge for 4 hours.
1 bulb fennel
Closer to serving, again using a vegetable peeler or a mandoline, thinly slice or shave the zucchini into ribbons. Add the zucchini to the bowl with the fennel and gently toss to coat in the vinaigrette. You can add a little more dressing if it needs it, but don’t drench it.
4 zucchini
To serve, gently place the zucchini and fennel on a platter, arranging it so it sits up high and curls. Top with the grated parmesan and mint leaves. Sprinkle with the chopped chives (if using). Drizzle some more dressing on top. Season well. Serve immediately.
4 zucchini, 0.5 cup parmesan cheese, 0.25 cup mint leaves, chives