Prep the tomatoes: Core and seed them to reduce extra liquid. Dice into small, even pieces.
Chop the onion: Finely dice for even distribution and a balanced bite.
Handle the heat: Mince the jalapeño or serrano.
Remove seeds and membranes for mild salsa; keep some for more heat.
Chop the cilantro: Roughly chop leaves and tender stems for maximum flavor.
Mix it up: In a bowl, combine tomatoes, onion, chili, cilantro, and garlic (if using).
Season: Add lime juice, salt, and a pinch of black pepper. Toss gently to combine.
Taste and adjust: Add more lime or salt as needed. If it tastes flat, it likely needs a pinch more salt.
Rest briefly: Let it sit 5–10 minutes so the flavors meld.
Stir again before serving.