- Bring a large pot of salted water to a boil. Add 8 oz elbow macaroni and cook according to the package instructions until al dente. Drain the pasta using a colander and set aside. 
- In a large skillet over medium heat, add 1 lb of ground beef. Break it up with a spatula and cook until browned and cooked through, about 7-8 minutes. Drain excess fat if necessary. 
- Sprinkle 1 packet of taco seasoning over the cooked beef. Stir in 1 can diced tomatoes with green chilies (including the juice). Let the mixture simmer for 3-4 minutes to blend the flavors. 
- Add 1 can of black beans (drained and rinsed), 1 cup corn, and 1/2 cup sour cream to the skillet. Stir well to combine all ingredients. Season with salt and pepper to taste. 
- Transfer the cooked elbow macaroni into the skillet or a large mixing bowl. Add 2 chopped green onions and stir everything together until well combined. 
- Preheat your oven to 375°F (190°C). Transfer the pasta mixture into a greased 9x13-inch baking dish. Sprinkle 1 cup shredded cheddar cheese and 1 cup shredded mozzarella cheese evenly over the top. For an extra spicy touch, scatter 1/2 cup sliced jalapeños on top (optional). 
- Place the baking dish in the oven and bake for 20-25 minutes, or until the cheese is melted and bubbly with some golden spots. Remove from the oven and let it rest for 5 minutes before serving.