The Japanese have long enjoyed rice with barley. Cooking the grains uncovered in a substantial amount of water ensures a perfect texture every time. Hulled or semipearled barley (they’re the same) and canned adzuki beans are available at natural foods stores and some supermarkets.
Combine rice, barley and 3 cups water in medium saucepan. Bring to a boil, and add 1/4 tsp. salt. Reduce heat, and simmer, uncovered, about 30 minutes, or until water reaches level of grains. Reduce heat to low, cover and cook 5 minutes more, or until grains are dry. (Do not disturb steam holes that have formed.) Remove from heat, and let stand 5 minutes.
Meanwhile, heat ginger and sesame oil in medium skillet over medium heat until ginger begins to sizzle, about 3 minutes. Add beans, mirin, vinegar and remaining 1/2 tsp. salt. Cook over medium-high heat, stirring often, about 3 minutes, or until liquid evaporates.
Stir beans into cooked rice and barley. Taste, and add more salt if desired. Sprinkle with chopped green onions. Serve with Japanese Spring Vegetable Ragoût.