Defrost your garlic directly in the frying pan. Add your ground beef, brown and drain.
Add ground beef, macaroni, can of RO*TEL (I used Original no salt added), and beef broth to large pot. Stir, then heat to boiling. Reduce heat, simmer covered 12-15 minutes until macaroni is tender.
While the macaroni cooks prep the cheese sauce. Melt butter in a small saucepan. Add in flour, cooking until smooth and fragrant (~ 5 minutes). Whisk in the milk, then bring to a boil. Whisk consistently until mixture is thickened.
Remove mixture from heat. Add shredded cheddar cheese, stirring until fully melted. Season with salt and pepper. Pour cheese sauce over cooked Mac and hamburger. Stir until fully combined.