In a large skillet, cook the ground beef over medium heat until browned. Drain excess grease.
Add taco seasoning and stir in the beef broth. Let it simmer for 2–3 minutes.
In a separate pot, melt butter over medium heat. Whisk in flour and cook for 1 minute.
Gradually add milk, whisking until smooth. Cook until the mixture thickens.
Stir in shredded cheese and mix until melted and smooth.
Add uncooked macaroni to the beef mixture and bring to a simmer. Cover and cook for 10–12 minutes, stirring occasionally, until pasta is tender.
Pour the cheese sauce over the cooked pasta and beef, mixing well.
Season with salt and pepper to taste. Serve warm with optional toppings.