01 - Season the lamb pieces generously with salt and freshly ground black pepper.
02 - Heat 2 tablespoons of vegetable oil or unsalted butter in a large heavy-bottomed pot or Dutch oven over medium-high heat. Brown the lamb in batches, ensuring all sides are deeply seared. Remove the seared lamb and set aside.
03 - Add the chopped onions, sliced carrots, sliced parsnips, and sliced celery to the pot. Sauté for approximately 5 minutes, scraping up any browned bits from the bottom of the pot.
04 - Stir in the minced garlic and cook for 1 minute until fragrant.
05 - Return the seared lamb to the pot. Add the chunks of potatoes, bay leaves, fresh thyme sprigs, 4 cups of low-sodium beef or lamb stock, and 1 cup of water. Bring the mixture to a gentle boil, then reduce the heat to low.
06 - Cover the pot and simmer for 1.5 to 2 hours, stirring occasionally, until the lamb is exceptionally tender and the vegetables are thoroughly cooked.
07 - Carefully remove and discard the bay leaves and thyme sprigs. Taste and adjust the seasoning with additional salt and pepper as needed.
08 - Ladle the hot stew into serving bowls, garnish with chopped fresh parsley, and serve immediately.