In a medium sauce pan, brown ground beef with onion until onion is translucent and all the beef is brown and crumbly. Add garlic, Italian seasoning, & red wine and simmer for a few more minutes. Add jar sauce and canned tomato and simmer until ready to serve (at least 10-20 minutes?)
Optional: Remove from heat. Stir in spinach until wilted. Serve immediately.
IF freezing stir in spinach when reheating.