In a small bowl, mix mayonnaise and minced chipotle peppers. Cover and refrigerate until ready to serve.

Drain and rinse the beans, then pat dry. Add to a mixing bowl and mash well.

Add bell pepper, onion, cilantro, and garlic to a food processor; finely chop. Add in oats, egg, cumin, and sea salt; pulse a few times to mix, but do not puree. Scoop this mixture into the bowl with the beans and stir together. Shape into patties, then freeze patties for 2 hours.

Spray a skillet with cooking spray and heat over medium. Add patties and cook for 7-8 minutes, flipping halfway through cooking. Add to buns with chipotle mayo and sliced avocado. Serve with pineapple on the side.