Heat a dry skillet over high heat. Once hot, add the tomatoes, onion, and jalapeño. Don’t mix and let them start to get that nice char. Once you get some color on one side, mix and continue to cook until they are charred and blistering, adding the garlic closer to the end, for a total of about 10 minutes.
Remove the pan from the heat and let it cool slightly. Add all the charred ingredients to a blender with the cilantro leaves, lime juice, and 1/2 teaspoon sea salt. Pulse until the salsa is the consistency you like. Pour the salsa into a bowl. Stir in the diced fresh mango. Taste and season with more salt if needed. Cool to room temperature and enjoy with your favorite tortilla chips.