What makes this stew quick and good is the tempeh, which contributes long-simmered heartiness in record time. The shoyu gives the sauce an earthy color and deep, rich taste. When I serve this dish on its own, I like to cut the tempeh into "fingers" about one-third inch wide. If I'm planning to ladle the stew over spaghetti, I prefer to halve the tempeh horizontally and cut it into one-inch squares.