Preheat the oven to 425 degrees F. Arrange the halved tomatillos on a parchment lined baking sheet and roast until soft and charred, about 20 minutes.

Remove from the oven and cool. Transfer the tomatillos into a blender or food processor with the onion, jalapeño, garlic, cilantro, lime juice and salt. Blend until smooth. Taste and adjust seasoning with more cilantro, lime juice, or salt according to preference. Serve with tortilla chips.