adapted by http://theresalwaysthyme.blogspot.com
1/2 cup chopped white onion
2 or 3 chopped serrano chiles (more or less to taste, you can also use jalapeno)
1/4 cup chopped cilantro
salt and pepper, to taste
4 ripe avocados
juice of one lime
3/4 cup tomato, diced, seeded and drained well
Depending on how chunky you like, use a food processor and pulse to combine onion, chiles, cilantro, salt and pepper, or a molcajete if you have one. Or just a knife!
Coarsely mash the avocados. Fold in reserved onion mixture, then tomato. Serve with tortilla chips.