Aji (鯵), also known as horse mackerel, is a popular marine fish in Japan, belonging to the family Carangidae. It typically measures 20 to 30 cm in length and is a type of blue-backed fish. Aji has a beautiful sheen of silver and blue, with distinctive black spots along its sides. The best season for aji is mainly in summer, particularly from June to August, when it is at its tastiest. During this period, aji is rich in fat and has firm flesh, offering exceptional flavor. Aji is used in a variety of dishes, with its freshness highlighted in sashimi and sushi, which are very popular. It can also be enjoyed grilled with salt, dried, in nanbanzuke (a type of marinated dish), or tataki (lightly seared). Dried aji is easy to store and cook, making it a common choice in home cooking. Additionally, nanbanzuke, where fried aji is marinated in vinegar, soy sauce, and chili, offers a refreshing taste. Thus, aji is widely loved for its reasonable price and rich nutritional value, making it a staple in home cooking and izakaya menus. Its versatility in cooking methods and compatibility with various dishes add to its appeal.