I just got my fish handling, and feel your pain on the search for profits in cooking. My solution is to research prices and find niches that haven't been filled. I spent several hours last week checking AH prices and looking for opportunities, and I can tell you that there are some.(No, I'm not going to tell you what I found, because markets are competative

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Margins are very tight because there are tons of cooks and I don't make big profits at my lvl (62) unless i farm the ingredients. Farming elementals and buying mellons and berries means almost no overhead on yag juice and melon stuff. If elementals are too tough, you can garden the crystals, and also garden the ingredients. There are several good sites listed in the stickies atop this crafting board which can help you with gardening.
Also, by this time there are things which you can hq with some regularity, and that is where you will find those elusive profits. If you have a mule, you can focus on things with less margin that are popular and will sell fast, like pies and juices.
The advice I was given that has helped me most is to be flexible and patient. If the price on juice at AH goes up, make juices and sell them for less than AH price. Your profits will still be higher than normal, and you will move inventory quickly. Take juices and foods with you when you party and sell them from your bazaar. If someone is way the heck out in BFE and forgot their snacks, they will pay more than normal.
If you go for the Key Items, you can get into recipies which some cooks can't touch, but it takes a lot of time and money to get them, so don't expect REAL profit for a long time. I am going to advance my fishing skill to take advantage of the :fish handling:, and this is, I'm told, the holy land of profits for many cooks.
Edited, Fri Dec 23 20:19:27 2005 by RaefofFFXI Edited, Fri Dec 23 20:20:50 2005 by RaefofFFXI