Raku is a Japanese noodle shop on the East Side of New York that serves udon and mackerel sushi. Its representative menu items are chewy basic udon, tantanmen, and mackerel sushi, and the broth is on the rich side. When you order shrimp tempura udon, the tempura comes separately so it stays crisp. The space is small, so the tables in the middle are pushed together and you sit as if sharing them.