Cut the tomatoes in half and scoop out the seeds (this will prevent the salsa from getting too watery). Give them a regular chop (see how to chop, illustrated).
Peel the onions and give them a regular chop as well.
Grate the garlic.
Remove the seeds of the pimiento and chop. Yes, regular too.
Finely chop the cilantro and scallions.
Toss everything together. Add the lime juice and zest, and some salt. Stir. Taste. Adjust the seasonings, if needed.