All of the measurements are to my taste if you prefer more spice then add more jalapeño. The measurements are adjustable.
Chop tomatoes and finely dice the onion and jalapeño
Remove the avocado from skin.
Mash it up until desired consistency. I like mine fairly smooth.
Squeeze in lime juice and mix.
Add olive oil.
Add in salt and pepper to taste. And stir to combine.
Add in the tomatoes, onion, and jalapeño.
Fold them in gently.
To check for salt try with the vessel that you will be serving it with. In this case it was a tortilla chip. And enjoy!