Terminal 1 (All Airlines but Southwest)
360° Gourmet Burrito
Vegan options: You can get a salad or burrito with smoked tofu. It appears from their website that all of the sauces are vegan.
Vegetarian options: Any of the above with cheese and sour cream. Quesadilla options. Breakfast burritos with egg and cheese.
Website (For main menu - selections within the Oakland Airport may be more limited.)
There are also your run-of-the-mill snack bars with pre-made sandwiches and salads, which typically offer few, if any vegan choices. Breakfast is especially limiting with little more than fruit and bagels with jelly.
Terminal 2 (Southwest Airlines)
Andale (Mexican)
Vegan options: Mesquite Grilled Veggie Burrito
Vegetarian options: Above plus Huevos ranchers (Breakfast), Vegetarian Burrito (can be vegan without cheese), Quesadilla options
Website Note: I have contacted Andale to verify ingredients (namely that no chicken stock or lard are used in the cooking process) but I have not heard back.
California Pizza Kitchen
Vegan options: Tomato Basil Spaghettini, Thai Linguini, Grilled Vegetable Salad, Field Greens Salad. Some dishes may be vegan by requesting no cheese.
Vegetarian options: A large variety of meatless pizzas and pastas.
Website
Member Comments about this Airport
Airports rarely are if you're vegan, but Oakland especially if you're not flying Southwest has really limited options. I suggest trying to bring some food for home. I remember trying to get a tofu salad at 360 Burritos so I would have food for the plane but it was too early and they wouldn't make it for me.