Preheat your oven to 350°F (175°C).
Heat olive oil in a Dutch oven over medium-high heat. Brown the lamb shanks on all sides. Remove and set aside.
In the same pot, add the chopped onion and garlic. Cook until softened.
Pour in the red wine, scraping up any browned bits from the bottom of the pot. Let it simmer for a few minutes.
Add the beef broth, diced tomatoes, tomato paste, rosemary, and thyme. Stir well.
Return the lamb shanks to the pot. Season with salt and pepper.
Cover the pot and transfer it to the preheated oven. Cook for about 3 hours, or until the lamb is tender.
Serve the lamb shanks with the sauce spooned over the top.