Poke around in any South Asian grocery in Curry Hill, Jackson Heights, or Richmond Hill, and you'll find bags of spices at one-tenth what you'd pay for them in supermarkets, cheap nuts in bulk, and a section devoted to fats, some unfamiliar. There's coconut oil, sesame oil, and ghee, of course, a form of clarified butter used liberally and to good effect in the best Indian cooking. But you'll also find vivid yellow mustard oil. Pick up a bottle and read the label, and you might be discouraged to see: "For... More >>>