Cut the meat into large cubes and place it in a pot. Cover with water, add a little salt, and simmer until the water completely evaporates. Fry the meat in its own fat.
Criolla Sauce: Slice the onions lengthwise. Set aside. Dice the tomatoes into small cubes and mix them with the onions; season with vinegar, salt, and pepper as if making a salad. Sprinkle with chopped parsley.
Serve some pieces of meat accompanied by a bit of "criolla sauce" and a boiled potato.
