Brown ground beef and onion in a large skillet over medium-high heat for 8-10 minutes, breaking up meat as it cooks. Spoon out excess fat, leaving 1-2 tablespoons.
Stir in garlic and Italian seasoning, cook 30 seconds until fragrant.
Add diced tomatoes with juices, broth, heavy cream, and gnocchi to the pan and stir well.
Bring to a bubble, cover, reduce heat to medium, and cook 5 minutes.
Remove lid and stir, then cook uncovered 3-4 minutes more, stirring occasionally, until gnocchi is tender and sauce thickens.
Stir in parmesan cheese until melted.
Taste and season with salt and pepper as needed.
Serve immediately.