1/2 cup loosely packed chopped fresh cilantro leaves, divided
1/2 avocado, chopped
In a large oven-proof skillet on medium-high, bring tomatoes, milk and broth to a boil, stirring occasionally. Stir in pasta, cover and reduce heat to medium, adjusting as needed to maintain a steady simmer. Cook, stirring occasionally, until just barely al dente, 8 to 14 minutes.
Arrange oven rack in center position and preheat broiler to high. To skillet, add beans, corn, half of cheese and 5 tbsp cilantro. Stir until heated through, about 1 minute. Sprinkle remaining half of cheese over top and transfer to oven. Broil until cheese is melted, 1 to 2 minutes. Rest for 3 to 5 minutes. Divide among plates and sprinkle evenly with avocado and remaining 3 tbsp cilantro.