Preheat oven to 350 F.
Bring a large pot of water to a boil. Cook your macaroni, but for 3 minutes less than the box directions.
Heat a large skillet over high heat. Add the ground beef and onions. Break up the ground beef, cooking for 6 to 7 minutes until brown.
Drain any fat from the skillet, then mix in garlic and cook for 1 minute, until fragrant.
Add in Worcestershire sauce, tomato sauce, and diced tomatoes. Mix until combined.
Stir in Italian seasoning, salt and pepper.
Mix in the cooked macaroni and cheddar cheese. Transfer to a casserole dish and bake for 20-25 minutes, until bubbly and cheese has melted. You can bake in your skillet, if it is heat safe.