Barley Risotto with Leeks and Mushrooms

Traditional risotto transforms simple grains of starchy rice into a luxuriously creamy dish. We do something similar with barley. Pearled barley, the type used here, has had its husk and bran removed so the grains cook more quickly than whole-grain. To bring out a rich, nutty flavor in the barley, we toast it in olive oil before simmering.