Grilled Roma Tomato Salsa

I doubled this recipe. 1 pound Roma tomatoes, cored and halved 1/2 medium white onion, cut into 1/2-inch slices 2 medium garlic cloves, peeled and smashed 1 medium serrano chile, stemmed Put all vegetables in a roasting pan with olive oil, fresh cracked black pepper and other spices as desired. Cook indirect 550ish until tomatoes and onions are soft. 1 teaspoon kosher salt, plus more as needed 2 tablespoons coarsely chopped fresh cilantro 1 teaspoon freshly squeezed lime juice, plus more as needed Add all ingredients in blender.