Based on their price, nourishment via Realistic Needs and Diseases mod, and apparent deliciousness, I'd have to go with (in no particular order) apple pies, beef stew, grilled leeks, and braided bread. In terms of awesome buffs, Elsweyr Fondue is the obvious meal of choice for the aspiring wizard. Venison and veggie stews are right up there alongside beef stew in terms of stamina recovery.
And among modded foods, I have just gotta go with the RND & Frostfall compatible teas from Hunterborn. I love tea in real life, so my characters naturally love mountain flower tea every afternoon!