Combine all ingredients, adding salt and pepper to taste. Let sit for at least 10 minutes. Will keep, covered in the refrigerator, for 3 – 4 days.
Burgers
Combine flaxseed and water in a small bowl and let sit for 5 minutes.
Put the beans in a large mixing bowl. Mash with a potato masher until most of the beans are mashed with some chunks of beans left. Add the flaxseed mixture, breadcrumbs, onion, chipotles and sauce, cumin, and salt. Mix well. Form into 6 patties and refrigerate for 20 – 30 minutes.
Heat some oil in a large skillet over medium heat. Add the burgers and cook for 6 minutes per side.
Spread some mayonnaise on each bottom burger bun, add a lettuce leaf, the burger, and top with the salsa. Serve with pickles if desired.