Heat the olive oil in a large, deep skillet over medium heat. Sauté the onion for 4 minutes until translucent, add the garlic and sauté until fragrant.
Add the red wine and deglaze the pan, scraping up all the little brown bits.
Add the butter to the skillet and allow it to melt completely.
Add the can of tomatoes to a blender or food processor, blend until smooth. Add the onion and garlic mixture, basil and salt and pepper. Blend until smooth.
Transfer the sauce back to the skillet and allow it to simmer for 10-15 minutes, stirring occasionally.
To Bake
Grease a baking dish and add the gnocchi, cooked sausage and sauce, stir to coat. Top with cheese and broil until the cheese has melted.