Peel mango. Chop onion, tomatoes, and avocados. Only use the tomato skin. Combine all ingredients. Mash.
I normally hate cilantro, but it tasted great in the recipe. I bought a bundle of cilantro, and I believe I chopped up a good handful. Garlic was the special ingredient my friend added that brought out a lot of flavor and made it great. She had minced garlic in the fridge, and I believe she added around a teapoon.