Preheat the oven to 425 degrees F. Line a baking sheet with parchment paper. Place the tomatoes and cut limes on the sheet, drizzle with olive oil and cover with salt and pepper. Turn the limes cut-side down. Roast for 20 to 25 minutes, until the tomatoes are bursting and the limes are charred.

In a large bowl, mash together the avocado, jalapeno, onion, cilantro, the juice of 2 limes, salt and pepper. Taste and season additionally if desired. Stir in almost all over the tomatoes, squeeze in the lime juice and stir in almost all of the queso fresco. Top with the leftover tomatoes, cilantro and queso fresco. Serve immedaitely with chips!