Heat a nonstick skillet and brown the beef, breaking it up into 3/4 in or so crumbles. Drain off the fat.
Add the remaining ingredients, bring to a boil, reduce to a simmer, cover and cook for 20 minutes. Stir a few times. (I actually do this in a saucepan, as I found that it can burn too easily in the skillet).
Serve topped with shredded cheese, cilantro, or chopped green onions.