Preheat oven to 325 degrees.
Drain and rinse beans well. Pat dry. Spread beans on a lined baking sheet and bake for 15 minutes until slightly dried out. Reserve 1/2 cup black beans.
In a food processor, combine remaining beans, lime, onion powder, garlic powder, cumin, and parsley. Pulse until mixture comes together. Remove from processor and set aside.
In a food processor, combine poblano, onion, oats, and walnuts. Pulse a few times until you reach your desired consistency. I prefer a chunky texture, so I only pulse a couple of times.
In a large bowl, combine the bean mixture, oat mixture, the reserved 1/2 cup black beans, salt, and pepper. Stir until well combined.
Using a large cookie or ice cream scoop, scoop mixture, and form into patties. I used 2 scoops per patty. Place patties on a parchment or waxed paper-lined tray and freeze for one hour.
In a non-stick or cast-iron skillet, heat 1 Tbsp olive oil over medium heat. Place two frozen patties in skillet and cook approximately 4 minutes on each side. Cook remaining burgers, adding a little oil each time.
Serve warm and enjoy!