Step 1: Prepare Oven and Lamb Shanks

• Preheat oven to 325°F (160°C).

• Season lamb shanks generously with salt and pepper on all sides.

Step 2: Brown Lamb Shanks

• Heat olive oil in a large Dutch oven (at least 6-quart size) over medium-high heat.

• Sear lamb shanks in batches until browned on all sides, about 2-3 minutes per side.

• Transfer browned shanks to a plate and set aside.

Step 3: Sauté Vegetables

• In the same Dutch oven, add chopped onion, carrots, and celery.

• Sauté vegetables for 3-4 minutes until slightly softened.

• Add garlic and sauté an additional 3-4 minutes until vegetables begin caramelizing. Season lightly with salt and pepper.

Step 4: Add Herbs and Wine

• Stir in chopped sage, thyme, rosemary, and bay leaf. Cook 2 minutes until fragrant.

• Pour in red wine, scraping the bottom to loosen browned bits (this adds depth to the flavor). Simmer until the wine reduces by about half, approximately 2-3 minutes.

Step 5: Braising Liquid

• Stir in diced tomatoes (with juices) and chicken stock. Return lamb shanks back to the pot. (It’s fine if shanks slightly overlap.)

• Season the liquid gently again with salt and pepper.

Step 6: Braise in Oven

• Cover the Dutch oven with its lid, transfer to preheated oven.

• Braise lamb shanks for 2–2½ hours until meat is extremely tender and easily pulls away from the bone.

Step 7: Serving

• Remove pot from oven. Carefully transfer shanks to serving plates, ideally atop creamy mashed potatoes or polenta.

• Spoon generous amounts of the rich braising liquid over each lamb shank.

• Garnish with additional fresh thyme leaves and serve immediately.