Food and drink tend not to sell well, as provisioning is easy to level and many people make their own. Your best best are the new blue Wrothgar recipes or purple food.
Or, if we get a new tier of higher level recipes, for a while they will be hot items until the recipes become more widespread.
As NBrookus said, people can make their own so they don't typically sell very well. However, if you want to make some cash then try and either use the hirelings to sell ingredients or make good lower level food for <30levels (as there's less chance these have levelled provisioning) and sell on guild traders.