In a large skillet over medium heat, melt the butter. Add the uncooked gnocchi to the pan. Stir, breaking apart as you go, until it's in a single layer. Let the gnocchi cook about 2 minutes, until lightly toasted. Stir to turn the gnocchi, cooking again until the other side's lightly toasted too. Remove the gnocci to a plate, set aside.
Increase the heat to medium high. When the skillet's nice and hot, add the beef and onion, stirring to break up. Season liberally with salt and pepper, then stir in the cumin, paprika, mustard, and garlic until evenly combined. Continue cooking, stirring occasionally, until the ground beef is cooked. Drain the beef, and return to the pan.
Add the tomatoes, broth, and gnocchi to the beef mixture in the pan, stirring to evenly incorporate. Bring the mixture to a rolling boil, immediately reduce the heat to a simmer.
Cover the pan to seal, and let it simmer about 5-7 minutes, or until the gnocchi are completely cooked and most of the liquid's been absorbed.
Remove the lid from the pan, and remove the pan from heat. Let it rest 1-2 minutes. Stir in the cream and 3/4 cup of cheese until evenly combined and the cheese is melted.
Sprinkle the remained cheese evenly out over the skillet. Sprinkle half the green onions over top. Place the skillet under a broiler, watching carefully, just until the cheese is melted and golden brown on top.
Remove the skillet from the oven, and let the mixture rest for another minute. Scoop onto plates, top with the remaining green onions, and serve immediately.