In a large bowl, add jalepeno, onion, garlic cloves, and parsley.Cut avocados lengthwise, remove pits, and dig out flesh with a spoon. Add to bowl.Squeeze lime juice over the top of avocados.Add salt, pepper, and cumin to bowl.Use a potato masher to mash avocados to desired consistency.Test seasoning and add more salt or pepper as needed.Add tomatoes and stir with a spoon to make sure all contents are well combined. Serve immediately. (Note: If not eating right away, place plastic wrap on top of the surface of guacamole and put in fridge to slow oxidation.)