There are several ways to answer that, ranging from deflective to revealing; Neji opts for something in the middle. Chouji has been good to him, good enough that he won't do him the disservice of blocking him out entirely, but his natural reserve still holds strong.

"Coming from you, I would hardly call it 'the least,'" he points out quietly, meaning it; Chouji's cooking is excellent, and the communication of caring that comes with it is even more so.