It depends on your approach to cooking and ability to acquire materials, be it through farming and/or fishing.
If you have one character with max fishing (Levels and Gear):
https://www.ffxiah.com/item/5893/marine-stewpot
--> Also requires farming
https://www.ffxiah.com/item/5680/agaricus/?stack=1
If you have multiple fishing characters (Some can be level 0 fishing) and are able to catch a variety of fish:
https://www.ffxiah.com/item/6469/sublime-sushi-1/?stack=1
If you want to craft food strictly from vendor materials any of the daifukus are a great option:
https://www.ffxiah.com/item/6344/grape-daifuku-1/?stack=1
If you don't mind just buying materials on the AH many of the ramens are profitable:
https://www.ffxiah.com/item/6461/miso-ramen-1/?stack=1
https://www.ffxiah.com/item/6463/salt-ramen-1/?stack=1
If you prefer to farm some various or random materials that are rarely available, sell slower, but very high margins try things such as:
https://www.ffxiah.com/item/6602/om-sand-1?stack=1
Same applies to above, but isn't technically food but is made with cooking most all of the new BST jugs are either fishing or obscure farming materials:
https://www.ffxiah.com/item/17918/windy-greens
https://www.ffxiah.com/item/17917/bubbly-broth
https://www.ffxiah.com/item/17919/tant-broth
https://www.ffxiah.com/item/21439/venomous-broth
https://www.ffxiah.com/item/21473/feculent-broth
https://www.ffxiah.com/item/21471/putrescent-broth
No idea if any of this is helpful, but this is a quickly thrown together list from memory of many of the modern sought after foods.