Core and seed the tomatoes if desired, then finely dice them to yield about 2 cups. Finely dice the white onion to equal 1/4 cup. Remove seeds and membranes from the jalapeño (or leave some for more heat) and finely mince 1/2 of a jalapeño.

Combine and season

In a medium bowl combine the diced tomatoes, diced onion, minced jalapeño, and chopped cilantro. Add 1 tablespoon fresh lime juice, 1/2 teaspoon kosher salt, 1/8 teaspoon ground black pepper, and 1 teaspoon extra-virgin olive oil (optional). Stir gently to combine.

Rest and adjust

Let the salsa rest at room temperature for 10–15 minutes to let flavors meld. Taste and adjust seasoning with more salt, lime juice, or jalapeño as desired. If you prefer a smoother salsa, pulse 3–4 times in a food processor or blender for a chunkier-smooth texture.

Chips

If using store-bought chips, place 1 1/2 cups in a serving bowl. If you want warm or extra-crispy chips, preheat oven to 350°F (175°C). Lightly toss tortilla chips with 1 teaspoon vegetable oil (or spray) and spread in a single layer on a baking sheet. Warm in the oven 4–6 minutes until hot and crisp, watching carefully to avoid burning.

Remove chips from oven (if warming) and sprinkle with a light pinch of coarse sea salt if desired. Transfer chips to a serving bowl or plate.

Serve the prepared salsa in a separate bowl or spoon salsa over chips as preferred. Enjoy immediately so chips remain crisp.