In a food processor, combine salsa, cumin, salt, and black beans. Run until smooth. Stir in ½ cup bread crumbs and green onions.
Put the other ½ cup of bread crumbs in a shallow dish or plate. By hand (wet hands are best), form bean mixture into patties ½ inch thick, then dip each side in the bread crumbs before placing on a greased baking sheet. Bake for 14-16 minutes, flipping halfway through.
To prepare the toppings, simply combine the sour cream with the green onions in one bowl, and the avocado, tomato, and lime juice in another bowl.
Serve hot or cold with generous amounts of both toppings.
Recipe by The Kitchen Paper at http://c02.ddd.mwp.accessdomain.com/simple-black-bean-cakes/