One of the Japanese restaurant at basement 1 of NEX, under the big umbrella of Shokutsu 10, a Japanese food street concept outlet by the people behind Kuriya and Shimbashi Soba, otherwise known as RE&S.
Kabe No Ana claims to be THE original Japanese spaghetti house established since 1953. With over 80 varieties in their menu, you ought to find something you would like to try in there.
The pasta is decent though some may say its a bit dry for their liking. Add S$5 to your pasta for their soup and bread set. The bread that comes with it is nice!
Kabe No Ana
23 Serangoon Central