In a large pot over medium heat, add oil. Add onions, carrot, celery, and salt and cook until translucent, 3-5 minutes.
Add pepper and beef and saute until beef is mostly cooked through, 5-7 minutes.
Add garlic and cook for 30 seconds till fragrant.
Add red wine and deglaze the pan, scraping up any brown bits.
Add tomato puree and bring to a simmer. Cover and cook 45 to 60 minutes.
Cook gnocchi according to package directions (typically salted boiling water).
Serve gnocchi with ragu and optional toppings.