Cut the tomatoes into pieces and mash them roughly with a fork. Add the chopped onion. Finely chop the Jalapeño and mix it in. Squeeze the half lime and add a dash of its juice to the mixture. Add 1 teaspoon of chopped cilantro and a drizzle of olive oil. Season with salt, mix well, and refrigerate.
Preheat the oven to 180°C.
Place a sheet of greaseproof paper in a round dish about 20 cm in diameter.
Place half of the tortilla chips at the bottom of the dish. Sprinkle with half of the mozzarella diced, then repeat with the remaining chips and mozzarella.
Bake for 10 to 15 minutes. The cheese should be melted but not browned.