I have tried making vegan patties once or twice, and found it very hard to get them to stick together. They tasted good, but became sort of a toasted vegetable-bean pile. Vegetarian non-vegan can be delicious. Egg as binder, black beans, lots of onion and fresh garlic, carrots, maybe some long shredded green bean or bell pepper, mushrooms, maybe shiro miso paste for more savory, cheese if desired, they can be every bit as good as meat. Just not these weird soybean-carrot-broccoli-gluten things they make... very bland and pasty.