This is by far my favorite salsa. I got the recipe from my friend's husband, who is from Mexico.
I'm going to list the ingredients but not amounts because the fun part is you can add more or less of things depending on your tastes or even how much you have.
tomato (great way to use up those garden tomatoes)
onion (I used red but have done with white etc.)
chopped garlic (mine comes from a jar)
jalapeno pepper (or substitute - I used a small amount of hot chili pepper from my garden)
lime juice (I've made this with both a little lime and a lot and it's great both ways)
Just chop it all up, mix and enjoy!