Seeing as Jazz is a competent cook I will exclude them from the running. Arya is a bad cook in comparison to his confidence in the matter, but I don't think anything he'd serve would be deleterious as much as it would just be /awful/ (assuming nothing is set on fire.) Harley would make a mess simply because of their shape, but they'd likely make something acceptable, if basic. Because Avery isn't affected by capsaicin save a little bit of tingling, I could definitely see them utterly unable to balance spices and wind up getting someone sensitive to them in hot water.