Begin by finely chopping the vegetables, including mushrooms, carrots, broccoli, onion, and garlic. Place them on a baking sheet and roast in the oven until they are tender and slightly caramelized.
Mushrooms, Carrots, Broccoli, Onion, Garlic
Meanwhile, take the black beans and spread them on a baking sheet. Roast them in the same oven until they become crispy and dry.
Black beans
In a large mixing bowl, combine the roasted vegetables, black beans, spinach, walnuts, breadcrumbs, eggs or flax eggs, tomato paste, and cooked rice. Mix well until all the ingredients are evenly distributed.
Spinach, Walnuts, Breadcrumbs, Eggs or flax eggs, Tomato paste, Cooked rice
Take a handful of the mixture and shape it into a patty using your hands. Repeat this process until all the mixture has been used and formed into veggie burger patties.
Heat some olive oil in a skillet or barbecue grill. Cook the veggie burger patties for about 5 minutes on each side, or until they are golden brown and heated through.
Once cooked, serve the veggie burger patties on a bun with your favorite toppings and condiments.