Preheat oven to 425 degrees F. Spray baking sheet with cooking spray.
Empty 1 can of beans into colander over a bowl to collect the liquid. Donot discard liquid.
Once beans are fully drained, spread them in one layer on baking sheet. Place in oven for ~13 mins, until beans begin to split apart.
Chop up 1/2 onion and 3 cloves garlic. Saute with 1 tbsp extra virgin olive oil.
Season with salt and pepper. When onions start to brown, deglaze pan with 11/2 tbsp soy sauce and ½ tbsp of maple syrup.
Set aside 1/2 sauteed onions. Place remaining half in food processor and pulse 3-4 times. Dump into a large bowl.
Add 1/3 cup of walnuts to food processor and pulse 5-6 times and place in large bowl with onions.
When beans are cooked and out of the oven, place in food processor and pulse ~15-17 times until they have consistency of small pebbles. Add to large bowl.
Add rice, 1-2 tbsp potato starch, 1/2 tbsp onion powder, 1 tbsp garlic powder, ½ tbsp chili powder and 2 tbsp reserved liquid from can of beans.
Mix with a spoon or your hands until a "dough" forms. Quarter the dough and divide into 4 pieces. Shape each piece into a thin patty.
Dredge each patty in potato starch, coat with reserved bean liquid, and then coat with bread crumbs. Set aside in refrigerator.
Julienne 1 carrot, ½ cucumbers, and 2-3 cabbage leaves and place in a large bowl. Add 1 tbsp mustard and 1 tbsp maple syrup, together with salt and pepper. Mix.
Add 2 tbsp extra virgin olive oil to a large pan over medium high heat.When pan is hot, add patties (do not crowd pan).
Cook for ~5 mins and flip. Add cheese to each patty. Cook on stovetop with lid on the pan to melt cheese OR place in the oven at 450 degrees F for 3-4 minutes.
Assemble by adding patty to bun, topped with caramelized onions and slaw. Serve with your favorite side dish (fries, duh).