1 pound Roma Tomatoes, cored and halved ½ medium White Onion 2 medium Garlic Cloves 1 medium Serrano Chile, stemmed 1 teaspoon Kosher Salt 2 tablespoons chopped Cilantro 1 teaspoon Lime Juice
Arrange a rack in the upper third of your oven, than turn your oven broiler on 500. Place the Roma Tomatoes on a baking sheet, skin side up. Cut the White Onions into small slices, and peel and smash the Garlic Cloves. Scatter the Onions, Garlic and Chile around the Tomatoes. Place the baking sheet under the broiler until the Tomato skins start to blacken and blister. Remove from the oven and add them all to a blender, add the Salt and blend under desired smoothness. Transfer that to a medium bowl to let cool to room temperature, and then stir in the Cilantro and Lime Juice. May add more Salt and / or Lime Juice for your taste.