The best burgers! Mark Bittman has a lot of great vegan and vegetarian recipes. You can find lots of them in The New York Times, and he's written many cookbooks.
The recipe calls for an egg, but you can just leave it out. The burgers might be a bit more crumbly, but they're still great. Or use a vegan substitute such as soy flour or tapioca flour. (Here are some common egg substitutes.)
Mark Bittman's Nut Burgers