Add all the dressing ingredients together and mix well. Season and adjust to taste.
Preheat the oven to 200 degrees. Spread the sweet potato on a roasting tray, drizzle with some olive oil and season well. Roast for approx. 25 mins, until golden and cooked through. Remove and let cool.
To a large bowl, add the spinach, sweet potato, chickpeas, mango, avocado and cashews. Toss everything together.
Drizzle over the dressing and toss salad together.
