Motsu refers to offal, from the intestines and stomach to the tongue of the cow. Japanese people like to eat motsu for the variety of textures each organ provides. It’s popular with health-conscious diners who believe that offal provides a rich source of collagen—a popular nutritional supplement in Japan for maintaining a smooth and supple complexion. Common ways to enjoy offal in Japan include motsunabe, motsu simmered in a miso-flavored stew or in a spicy hotpot à la Kyushu-style, and motsuyaki, motsu grilled with salt or sauce.