This vegan butter burger is absolutely delicious. It can be made as greasy, gooey, cheesy comfort food ... there's also a healthier option without butter or oil and it's still delicious. Both versions are simple to make using commonly available ingredients.
Cook the rice according to directions and set aside.
Saute the mushrooms in a dry pan to brown and remove most of the moisture. Optionally, use a bit of butter for this step, if desired.
Drain the beans well, rinse them, and pat as dry as possible with paper towels.
Add the rice, mushrooms, beans, oats, and seasonings to a food processor. Pulse several times to mince and combine the ingredients. Don't overprocess.
Let burger mixture rest for about 20 minutes. Meanwhile, saute the onions in a large skillet with 2 tbsp vegan butter over medium heat until brown and tender.
Remove the onions and set aside. Fry the burgers in the remaining vegan butter, adding more if necessary. Cook about 4 minutes over medium heat on each side. Turn once.
Add a slice of your favorite vegan cheese to the tops, if you like. Steam some buttered vegan buns in the pan with the lid on for a minute or two while melting the cheese.
Serve on the buns topped with the buttery onions.