For the shell, pull apart 12 leaves from heads of romaine (pull out the ones near the center, because they're the crunchiest). Rinse and drain over a paper towel.
For black beans: Cook in their juice in a saucepan over medium heat for a few minutes. Drain and return to saucepan. Spray with Bragg's liquid amino acids. Add cayenne, chili powder, and cumin to taste. Stir and reheat until heated through.
For frozen corn, if using: In a saucepan, bring a little layer of water to a boil. Add about a half a bag of frozen corn. Put a lid on it and simmer until warmed.
Layer romaine leaves with black beans, then corn, then tomatoes, then avocado chunks. Drizzle salsa on top and serve.