Preheat your oven to 350°F (175°C).

Cook the macaroni according to the package directions until just al dente. Drain thoroughly and set aside.

In a large bowl, combine the ground beef, finely chopped onion, minced garlic, egg, breadcrumbs, Worcestershire sauce (if using), salt, and pepper. Mix until evenly combined but avoid overmixing.

In a separate bowl, stir together the cooked macaroni, shredded cheddar, and milk until the cheese begins to meld with the pasta.

In a lightly greased baking dish, press half of the meat mixture evenly across the bottom.

Spoon the macaroni-and-cheese mixture over that layer, spreading gently.

Top with the remaining meat mixture and smooth the surface.

Bake for 45 to 50 minutes, or until the meat is cooked through and the casserole is bubbling. Check the meat’s internal temperature with an instant-read thermometer; it should reach 160°F (71°C).

Let the casserole rest for 10 minutes before slicing.