In a large skillet, heat oil (1 tablespoon) until it shimmers. Add the sausage (16 ounces) and onion (1/4 cup), sautéing and crumbling sausage, over medium heat, until the sausage is lightly browned, for about 7-10 minutes.
Stir in garlic (1 tablespoon) and continue to sauté, stirring frequently, until garlic is fragrant, about 1 minute.
Pour in the wine (1/3 cup), and continue to cook, stirring frequently, until the wine has reduced and there's no longer liquid in the pan.
Stir in the sun dried tomatoes (1/3 cup), diced tomatoes with the juice (1 can), Italian seasoning (2 teaspoons), cream (1 cup), and gnocchi (16 ounces). Bring mixture to a simmer, cover the pan, then reduce the heat to medium-low and cook for 5 minutes.
Uncover the pan, stir in parmesan (1/2 cup), and continue to simmer, stirring often so the cheese doesn't stick to the bottom of the skillet, and until the gnocchi is cooked through to the tenderness you prefer. Taste and adjust salt and pepper if needed.
Remove from heat, stir in spinach (5 ounces), and cover. When the spinach is cooked (from the residual heat of the pan) serve!