Cooking (and baking!) without oil is easy.
Here's a quick video (below) of how to cook and saute without oil. My secret? vegetable broth! However, you can also use water (but broth is better!)
You can find my DIY recipe for vegetable broth in any of my cookbooks.
If you're using store-bought vegetable, look for low sodium varieties and make sure there are no oils in the ingredients. Even some of the advertised "fat-free" broths contain oil. A reminder that you never want to believe what you read on the front of a package!
For more information and tips, see my posts, " How to Replace Oil in Cooking " and " How to Replace Oil in Baking ."
Happy (healthy!) cooking!