Preheat oven to broil. Cut tomatillos in half from the top and place on greased cookie sheet along with habaneros, onion, and garlic. Broil until each veggie is charred over most of the skin. Caution: The garlic might char before the other veggies, if so, remove them first and replace the remaining veggies in the broiler until theyre done. Remove and let cool for a few minutes.