Mix mango nectar, water, vinegar and spices in a large bowl with wire whisk until well blended. Add basil seeds; mix well.
Refrigerate at least 1 hour before serving to allow basil seeds to hydrate and flavors to blend. Whisk dressing before serving.
Test Kitchen Tip: Basil seeds are black, tear-shaped seeds that, like chia seeds, have a gelatinous outer layer when wet. Also called Sabja seeds, they are the seed of the sweet basil plant native to India. Basil seeds absorb and take on accompanying flavors and provide texture and body without adding oils or fats, making them a great addition to smoothies, sauces, and dips. They can be purchased from specialty and natural food stores as well from many online retailers.