Bring a large pot of salted water to a boil. Add the elbow macaroni and cook according to package instructions until al dente. Drain and set aside.
In a skillet, heat olive oil over medium heat. Add the chopped onion and minced garlic, sautéing until the onion becomes translucent, about 3-4 minutes.
Add the ground beef to the skillet. Cook until it's browned and cooked through, breaking it up into smaller pieces, approximately 5-7 minutes. Drain any excess fat.
Stir in the diced tomatoes, Worcestershire sauce, Italian seasoning, salt, and pepper. Mix well and allow to simmer for 2-3 minutes.
Reduce the heat to low and slowly add the milk to the beef mixture. Stir in 1 cup of the shredded cheddar cheese until melted and creamy.
Add the cooked macaroni to the skillet, stirring until well coated with the cheese sauce.
Optionally, transfer the mixture to a casserole dish, sprinkle the remaining 1 cup of cheddar cheese on top, and broil for 2-3 minutes until cheese is bubbly and golden.
Serve immediately and enjoy your Cheesy Macaroni and Beef.