Sometimes labeled queso asadero or queso chihuahua, Oaxacan string cheese is a melting cheese available in balls, braids, or rounds. You can substitute mozzarella or Monterey Jack. Serve this dish with warm corn tortillas for dipping.
1 1/4 lb. fresh tomatillos, husked and rinsed
1 jalapeño chile, halved and seeded
1/3 cup packed cilantro
3 garlic cloves, peeled
2 tbsp. olive oil
1/2 large white onion, sliced
3/4 cup lower-sodium chicken broth
3/4 tsp. sugar
Salt and freshly ground black pepper
1 1/2 pounds queso oaxaca, cut into 6 portions
1. In a heavy medium saucepan, bring 2 cups water to boil iover medium-high heat. Add tomatillos and jalapeño and cook until tomatillos are tender, about 7 minutes. Using a slotted spoon, transfer tomatillos and chile to blender. Add 1/2 cup of the cooking liquid, cilantro, and garlic. Puree until sauce is almost smooth.
2. In a large heavy skillet, heat oil over high heat. Add onion and cook until beginning to soften, about 5 minutes. Add tomatillo sauce. Reduce heat to a simmer and cook, stirring occasionally, until sauce thickens, about 5 minutes. Stir in broth, sugar, and salt and black pepper to taste.
3. Heat a large nonstick skillet over high heat. Add cheese and cook until slightly browned, about 1 minute per side. Bring tomatillo sauce to simmer. Add cheese to sauce and cook until cheese begins to melt, about 2 minutes. Transfer cheese with sauce to shallow platter or divide cheese and sauce among 6 individual gratin dishes.