Bring a large pot of salted water to a boil. Add 8 ounces of penne pasta and cook according to package instructions until al dente (about 9-11 minutes). Drain the pasta and set aside.
Heat 1 tablespoon of olive oil in a large skillet over medium-high heat. Add 1 pound ground beef and cook until browned, breaking it up with a spatula. Drain excess fat if needed.
Sprinkle the taco seasoning packet over the beef, stirring well to coat evenly. Add 1 can rinsed and drained black beans, 1 can diced tomatoes with green chilies, and 1 cup corn kernels. Stir and simmer for about 5 minutes.
Preheat oven to 375°F (190°C). Combine cooked penne pasta with the beef and veggie mixture in skillet or large bowl. Stir in 1 cup salsa and 1/2 cup sour cream until well blended.
Transfer the mixture into a 9x13 inch baking dish. Sprinkle 1 cup shredded cheddar cheese and 1 cup shredded mozzarella cheese evenly over the top.
Bake in preheated oven for 20-25 minutes, or until cheese is melted, bubbly, and lightly golden.
Remove from oven and sprinkle 1/2 cup diced green onions and 1/4 cup chopped fresh cilantro over the top. Serve hot and enjoy!