In a large skillet, heat the olive oil over medium heat until shimmering.

Saute the onion until soft and translucent. Add the garlic and cook until fragrant but not browned, about 20 to 30 seconds.

Add the ground Italian sausage and cook until no longer pink, breaking up into crumbles with the back of a wooden spoon.

Pour in the red wine and scrape off any brown bits at the bottom of the skillet.

Add the tomatoes, stir, and let boil for 1 minute. Stir in the parsley. Season with salt and pepper to taste.

Serve over your favorite cooked pasta and garnish with fresh parsley and Parmesan cheese, if using.