Step 1: Cook the Beef and Aromatics

1. Heat a large pot or Dutch oven over medium heat. Add the ground beef and cook, breaking it apart with a wooden spoon, until browned, about 5–7 minutes. Drain excess grease if necessary.
2. Add the diced onion and garlic to the beef, cooking for 2–3 minutes until softened and fragrant.

Step 2: Add the Liquid and Pasta

1. Stir in the taco seasoning, coating the beef and onion mixture evenly.
2. Add the diced tomatoes (with their juices), beef broth, milk, and uncooked pasta to the pot. Stir well to combine.

Step 3: Simmer the Pasta

1. Bring the mixture to a gentle boil, then reduce the heat to low. Cover the pot and let the pasta simmer for 12–15 minutes, stirring occasionally to prevent sticking.
2. If adding frozen corn, stir it in during the last 5 minutes of cooking.

Step 4: Finish with Cheese

1. Once the pasta is tender and the sauce has thickened, remove the pot from the heat. Stir in 1 cup of shredded cheese until melted and creamy.
2. Top the pasta with the remaining cheese, allowing it to melt on top before serving.

Step 5: Add Toppings and Serve

1. Serve the pasta in bowls and garnish with fresh cilantro, sour cream, diced tomatoes, and green onions. Enjoy immediately!