Lettuce is not exactly a staple in Japan, but it's common enough that you'd have to go out of your way to avoid it. It's in sandwiches like you'd expect, it's i

Lettuce is not exactly a staple in Japan, but it's common enough that you'd have to go out of your way to avoid it. It's in sandwiches like you'd expect, it's in garnish, it's in salad (though the Japanese seem to prefer cabbage-based salad), and you can buy it at any supermarket.