Prepare the Lamb Shanks: Preheat your oven to 325°F (163°C). Pat the lamb shanks dry with paper towels and season generously with salt and black pepper.

Brown the Lamb Shanks: In a large oven-safe Dutch oven or heavy-bottomed pot, heat the olive oil over medium-high heat. Brown the lamb shanks on all sides until deeply golden (about 8-10 minutes). Remove the shanks and set them aside.

Sauté the Vegetables: In the same pot, add the chopped onion, garlic, carrots, parsnips, and potatoes. Sauté for about 5 minutes, stirring occasionally, until the vegetables begin to soften and the onions are translucent.

Deglaze the Pot: Stir in the tomato paste, cooking it for a minute until it darkens slightly. Then, pour in the red wine to deglaze the pot, scraping up any browned bits from the bottom of the pot. Let the wine reduce by half, about 5-7 minutes.

Add Broth and Herbs: Pour in the beef or lamb broth, and add the rosemary, thyme, bay leaf, cumin (if using), and paprika (if using). Bring the mixture to a simmer.

Braise the Lamb Shanks: Return the lamb shanks to the pot, nestling them among the vegetables. The liquid should come about halfway up the lamb shanks. Cover the pot with a tight-fitting lid and transfer it to the preheated oven.

Cook the Lamb: Braise the lamb in the oven for 2 to 2.5 hours, or until the meat is very tender and easily pulls away from the bone. You can check the tenderness by gently tugging on the meat with a fork.

Serve: Once the lamb is done, remove the pot from the oven. Discard the bay leaf and herb stems. Serve the lamb shanks hot with the vegetables and sauce from the pot, spooning some of the braising liquid over the top for added flavor.