Organic Mustard Brown (Brassica Juncea) is an indispensable ingredient in any cook’s larder. Whole black mustard seeds, either dry roasted, or “tempered” in a hot oil with fresh curry leaves, show off their nutty character in southern Indian cooking. Once ground, mustard seed releases its warmth, earthiness and pungency. Smooth mustard brings a kick to otherwise mild and cuddly dishes. Powdered mustard is simply finely ground mustard seed. They are harvested from mid February to mid April and called Rai in Hindi.