In a medium bowl, combine the diced tomato, onion and jalapeno.
Zest the lime with a microplane and measure about 1/2 teaspoon of zest. Add to the tomato mixture. Squeeze about 1 tablespoon of lime juice from the lime and add it to the pico de gallo mixture.
Add fresh cilantro and toss to combine. Taste for seasonings and add salt and pepper as desired. Serve immediately. Can be refrigerated in an airtight container for 1-2 days... beyond that the tomatoes will start to degrade.