Add ground beef to a large skillet over medium heat. Cook, stirring regularly, until the ground beef is no longer pink.
1 pound lean ground beef
Stir in the onion, and cook for 3-4 minutes, or until softened.
1 cup diced onion
Add broth, tomatoes, milk, pasta, and black pepper.
4 cups reduced-sodium beef broth or chicken broth, 14 ounce can diced Italian tomatoes, 1 cup milk, 16 ounces dry macaroni noodles, ½ teaspoon pepper
Bring to a boil.
Once at a boil, lower the heat to medium-low.
Cover and cook for 15 minutes, or until the pasta is al dente, stirring occasionally.
Remove from heat.
Add the cheese, and stir until melted and combined.
4 cup shredded Cheddar-Jack cheese
Season with additional salt and pepper to taste.
Notes
Ground beef: I like to use lean ground beef. If you use ground beef with higher fat content, drain it before adding in the onion. You could also use ground turkey or ground chicken. If using either of those, increase the seasoning.
Onion: White onion or yellow onion works well.
Broth: I recommend using reduced-sodium broth so you can better control how much salt there is in your dish.
Italian diced tomatoes: Or use regular diced tomatoes + 1/2 teaspoon of Italian seasoning.
Cheese: You can use any shredded cheese that you'd like. Shredded cheddar cheese works especially well.