Prosciutto Ham & Swiss Cheese Butter Bun 生ハム&スイスチーズのソルトバターパン Our popular salted bread is filled with prosciutto ham, Swiss cheese, and arugula greens. The bread is made with mellow natural rock salt, and the subtle saltiness of the prosciutto not only makes it delicious, but also helps to soothe fatigue. Give it a try.