I'll second or third Laurel's Kitchen and Moosewood Garden. I still have my extremely well loved Laurel's kitchen and go there all the time for inspiration, and I've never had a bad meal from Moosewood Gardens. They were the first books that set me on a path of better eating.
Recently, while I still consult them, I have a few new ones, including Vegetarian Cooking for Everyone, in part because it explains so many of the techniques - including knife skills, along with having a ton of recipes, and a brand new addition, Vegan with a Vengance, because the recipes are great, the notes are wonderful, and it is a good read even when you are not preparing to make food....it's even got me thinking about starting a Food Not Bombs group here locally.
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