Preheat your oven to 350°F (175°C).

In a large skillet, heat olive oil over medium heat. Add chopped onion and minced garlic, and sauté until onion is translucent.

Add ground beef to the skillet, cooking until browned. Drain excess fat.

Stir in diced tomatoes, beef broth, elbow macaroni, and Italian seasoning. Bring to a simmer and cook for 10 minutes until macaroni is tender.

In a saucepan over medium heat, melt butter. Stir in flour and cook for 1 minute to create a roux.

Gradually add milk, whisking continuously until the mixture thickens. Stir in shredded cheddar cheese until melted and smooth.

Mix the cheese sauce into the beef and macaroni mixture until well combined.

Transfer the mixture to a greased baking dish. Mix bread crumbs and parmesan cheese and sprinkle over the top.

Bake in the preheated oven for 20 minutes, or until the top is golden brown and bubbly.