In a large skillet, heat the olive oil over medium heat. Add the diced onion and minced garlic, sautéing until the onion becomes translucent, about 3-4 minutes.
Add the ground beef to the skillet, breaking it apart with a spatula. Cook until browned and no longer pink, about 5-7 minutes. Drain excess fat if necessary.
Stir in the diced tomatoes (with juices), beef broth, and Italian seasoning. Bring the mixture to a simmer.
Add the elbow macaroni to the skillet, stirring to combine. Cover and cook for about 10-12 minutes, or until the pasta is al dente, stirring occasionally.
Reduce the heat to low and stir in the heavy cream. Cook for an additional 2-3 minutes until heated through.
Remove from heat and stir in the shredded cheddar cheese until melted and creamy. Season with salt and pepper to taste.
Garnish with chopped fresh parsley before serving.