Brown and drain hamburger meat. Stir in taco seasoning, Rotel, beef broth, and macaroni. Heat to boiling. Reduce heat and cover pan. Simmer 12-14 mins until macaroni is tender.
FOR THE CHEESE SAUCE
Melt the butter in a saucepan. Whisk in the flour and cook, whisking for 5 minutes until fragrant and light brown in color. Add the milk and bring to a boil. Whisk until smooth and thickened.
Remove from heat and stir in the shredded cheddar cheese until melted. Add the salt and pepper to the cheese sauce.