Heat oil in a large Dutch oven over medium-high. Add sausage, onion, garlic, and Italian seasoning and then cook, stirring often and breaking up meat using a spoon, until meat is no longer pink, about 8 minutes.
Stir in tomatoes and broth and then bring to a gentle boil over medium-high.
Add gnocchi and spinach and then cook, stirring often, until gnocchi is al dente , about 2 minutes.
