01 - Combine vegan mayonnaise, minced chipotle peppers, adobo sauce, lime juice, and salt in a small bowl. Mix thoroughly, cover, and refrigerate until serving.
02 - Place drained black beans in a large bowl. Mash with a fork or potato masher until partially broken down, leaving some whole beans for texture.
03 - Add red onion, garlic, rolled oats, breadcrumbs, cilantro, tomato paste, cumin, smoked paprika, chili powder, salt, and black pepper to the mashed beans. Mix until evenly distributed.
04 - Divide mixture into 4 equal portions. Shape each portion into a burger patty approximately 1/2 inch thick. If mixture feels too sticky, add additional breadcrumbs 1 tablespoon at a time.
05 - Heat olive oil in a large skillet over medium heat. Place patties in the pan and cook for 4-5 minutes per side until golden brown and heated through. Transfer to a plate lined with paper towels.
06 - Lightly toast burger buns in the skillet for 1-2 minutes until golden, if desired.
07 - Spread chipotle mayo on both bun halves. Place a cooked patty on the bottom bun. Layer with lettuce, tomato slices, red onion rings, and avocado. Top with the upper bun and serve immediately.