In a small frying pan, dry-fry the cumin and coriander seeds for 30 seconds or until fragrant.
Cool and then grind in a mortar and pestle or spice grinder. Place into a large mixing bowl with
the red wine vinegar, olive oil, garlic, harissa and orange flower water. Whisk to combine.
Blanch the carrots in boiling salted water for 5 minutes, until almost tender. Drain into a
colander and allow to sit for a few minutes until they dry. While still hot, add to the red wine
vinegar dressing, and toss gently to coat. Allow to cool to room temperature, for the dressing to
infuse into the carrots. Add the green olives and mint. Season well and toss gently to combine.
Serve on the watercress leaves.