1. Remove the mango flesh from one side of the pit and roughly chop. Cut the remaining flesh into small dice and set aside. Place the roughly chopped mango, oil, vinegar, lime zest and half of the lime juice in a blender and blend until smooth. Season with salt and pepper.
2. Put the chayote in a large bowl and toss with the remaining lime juice. Add the carrots, onions cilantro and mango vinaigrette and toss to coat. Add additional salt and pepper to taste.
3. To serve, garnish with the reserved diced mango and additional whole cilantro leaves if desired.
To make cutting the chayote and carrots into matchsticks faster and easier, try using a Japanese or French mandolin fitted with a julienne blade.