in a large mixing bowl, combine the rolled oats and vegetable broth. let the mixture sit for 3-5 minutes, or until the oats have absorbed the broth.
while the oats are soaking, in a separate pan over medium heat, sauté the grated carrots, chopped mushrooms, chopped spinach, and diced onion until softened.
add the sautéed veggies to the mixing bowl with the oats.
next, add the tomato paste, nutritional yeast, garlic powder, onion powder, salt, and pepper. mix everything together until well combined.
form the mixture into 8 evenly-sized patties.
preheat your oven to 375 f (190 c) and place the patties onto a baking sheet lined with parchment paper.
bake for 25-30 minutes, or until the burgers are firm and crispy on the outside.
once done, remove from the oven and allow the burgers to cool slightly before serving on buns with your favorite toppings.