In a large pot, cook the pasta shells according to the package instructions. Drain and set aside.

In a skillet, cook the ground beef over medium heat until browned. Drain any excess fat.

Add the taco seasoning and Rotel to the skillet with the beef, and cook for another 5 minutes.

Combine the cooked pasta, beef mixture, and Velveeta cheese cubes in the pot over low heat.

Stir until the cheese is fully melted and everything is well combined. Top with shredded cheddar cheese before serving.