Salsa de Piña Tatemada

We are loving cooking from Bricia Lopez' new cookbook called Asada: The Art Of Mexican Grilling--although we are taking the heat down several notches. This was a bif hit at a multiple protein grilled dinner we cooked. 3 garlic cloves, peeled 1 medium-size red onion, finely chopped (about 1 1/2 cups) 1 medium (about 3-pound) pineapple, peeled, cored, and cut into 3/4-inch-thick slices 2 fresh serrano chiles, stemmed 2 tablespoons fresh lime juice 1 teaspoon fine sea salt, plus more to taste 1/4 cup olive oil 1/2 cup finely chopped fresh parsley Preheat grill to high (450°F to 500°F). Place garlic cloves and onion on 2 separate pieces of aluminum foil; fold each to create sealed packets. Place packets directly on grill grate; cook, uncovered, turning occasionally, until garlic and onion have softened, about 15 minutes. Meanwhile, place pineapple slices and chiles on oiled grates. Grill, uncovered, until pineapple is well marked, flipping once, 3 to 5 minutes per side, and skin on chiles is evenly charred, flipping often, 5 to 6 minutes. Transfer to a cutting board, and let cool 5 minutes. Chop pineapple into 1/4-inch pieces and garlic and chiles to a mince, and transfer to a large bowl. Stir in grilled onion and lime juice. Set aside. Add chile paste to bowl with pineapple mixture. Stir in parsley, and season with additional salt to taste.