Depends on the level. Eventually if you get to VR5 or better and have the recipe you'll want red wheat and honeycomb since they are part of a pot for increased health/magica. I hoarded them for two weeks before I could make the food and I'm darn glad I did.

Do not know about add-ons. Don't use them. However there are useful lists out there of the various recipes. I used google to find them.

JessieColtub17_ESO wrote: »

http://esoui.com/downloads/info163-SousChef-ProvisioningHelper.html

This will help. It will show you which recipes you have not learned, and it will show you which recipes food is used in if have have learned them.

Cool, thank you!

Items you will find that are worth hanging on to...

Salt, pepper, honey comb, red wheat, onions...I am sure there are a couple more, but those are the big ones. Oats and Tomatoes only come from provisioner mail, which is worth having at 2/3.

I think I prefer to use uesp.net/wiki/Online:Provisioning_Ingredients to determine such things. I use a print of the improvement ingredients to determine what to put in the bank. As I read it, Oats, Pepper, Tomato, Saaz Hops, Canis Root and Jazbay Grapes should be the rarest ingredients, whether they are or not *shrug*.

It should be pointed out that at various locations you are going to find ingredients common to the other alliances without your character being able to obtain a recipe to use them. At North Beacon in Auridon for instance DC ingredients can be found. So you might want to take that into consideration too.