1. Preheat oven to 350F (175C).
2. Season the lamb shanks generously with onion powder, garlic powder, mustard powder, smoked paprika, cayenne pepper, 1 tablespoon + 1 teaspoon AP flour, black pepper, and coarse salt.
3. Drizzle olive oil in a large oven-safe pot or Dutch oven over medium-high heat. Sear the seasoned lamb shanks for 6 minutes, browning them on all sides. Remove the shanks and set aside.
4. In the same pot, add a bit more olive oil if needed, then add the whole head of garlic, chopped celery, chopped carrots, and large white onion. Sauté for 4 minutes until softened.
5. Stir in the tomato paste and cook for 1-2 minutes.
6. Pour in the red wine, scraping up any browned bits from the bottom of the pot. Bring to a simmer, then add the beef broth, rosemary sprigs, bundle of thyme, and bay leaves.
7. Return the seared lamb shanks to the pot, ensuring they are mostly submerged in the liquid.
8. Cover the pot with a lid and transfer to the preheated oven. Braise for 3 1/2 to 4 hours, or until the lamb is fall-off-the-bone tender.
9. Carefully remove the lamb shanks from the pot. Strain the braising liquid into a separate saucepan, discarding the solids (garlic head, vegetables, herbs, bay leaves).
10. Heat the reserved braising liquid over medium heat. Whisk in the 3 tablespoons of cold cubed butter until melted and emulsified, creating a rich sauce.
11. Serve the red wine braised lamb shanks with the sauce and garnish with fresh chopped parsley.
