With a peeler or paring knife, remove the peel and white pith from the lime, leaving just the flesh. Place onion, jalapeño, cilantro, lime, salt, and three of the tomatoes into the Vitamix container in the order listed and secure the lid. Start the blender on its lowest speed, then quickly increase to Variable 5. Blend for 10 to 15 seconds, using the tamper to press the ingredients towards the blades until ingredients are chopped. Stop machine. Remove lid and add the remaining tomatoes. Secure lid. Select Variable 5 and pulse until tomatoes are chopped. Do not over mix. Leave chunky. Serve with tortilla chips.