Preheat your oven to 160°C (320°F). Pat the lamb shanks dry and season generously with salt and pepper. Heat oil in your Dutch oven over medium-high heat until shimmering.
Place the shanks in the hot pan and sear for about 4-5 minutes per side until they develop a deep golden brown crust. Use tongs to turn, ensuring even browning. Remove the shanks and set aside.
Add chopped onions, carrots, and celery to the same pan. Cook over medium heat for 5-7 minutes, stirring occasionally, until the vegetables are fragrant and slightly caramelized around the edges.
Stir in minced garlic and cook for another minute until fragrant. Pour in the red wine, scraping up the browned bits from the bottom of the pan with a wooden spoon. Bring the wine to a gentle simmer and cook for 5 minutes to reduce slightly.
Return the browned lamb shanks to the pan, nestling them among the vegetables. Add thyme sprigs, bay leaves, and pour in enough stock to come halfway up the sides of the shanks. Bring the mixture to a simmer.
Cover the pan with a tight-fitting lid or foil, then transfer it to the preheated oven. Braise for about 2.5 to 3 hours, or until the meat is fall-apart tender and easily pulls from the bone.
Check the sauce occasionally; if it reduces too much, add a splash more stock. Once cooked, remove the pan from the oven and let the shanks rest in the sauce for about 10 minutes, uncovered, to deepen the flavors.
Skim any excess fat from the surface of the sauce if needed. Serve the lamb shanks hot, spooning the glossy, wine-infused sauce over each piece. Garnish with fresh herbs if desired and enjoy the tender, flavorful bites.
