This is a Japanese product with a Chinese name. Rayu or layu means "spicy oil" in Mandarin, and that is just what this is – finely ground chiles, orange peel, sesame seed, seaweed and sancho pepper suspended (requires vigorously shaking) in toasted sesame oil. A refined Japanese version of Chinese chile oil – terrific drizzled over noodles (soupy or not), on rice, gyoza dumplings, greens...