Heat the oil in a large heavy casserole pot over medium-high heat until it is very hot. Sprinkle the beef with salt and pepper, and, working in two batches to avoid overcrowding the pot, add the beef to the pot and cook for 6 minutes, or until the beef is brown. Transfer the beef to a bowl.

Add the onions, garlic, rosemary, and thyme to the same pot and cook for about 3 minutes, or until fragrant. Add the wine and tomatoes, stirring to scrape up the browned bits on the bottom of the pot. Simmer for 8 minutes, or until the wine has reduced by about half. Return the beef and accumulated juices in the bowl to the pot. Add the stock and bring to a gentle simmer. The beef should be just covered with the cooking liquid. Decrease the heat to medium-low. Place a lid on the pot and cook, simmering very gently and stirring occasionally, for 1½ hours.

Add the parsnips, carrot and turnip and return the lid to the pot. Simmer gently for about 1 hour longer, or until the vegetables are tender and the beef is tender enough to cut with a spoon. Using a slotted spoon, transfer the beef and vegetables to a bowl. Boil the cooking liquid over high heat for 20 minutes, or until it is reduced by half. Return the beef and vegetables to the pot and simmer gently just until they are heated through.

Meanwhile, to prepare the parsley potatoes: Bring a large pot of salted water to a boil over high heat. Add the potatoes and cook for about 18 minutes, or until just tender and a skewer can be inserted into the center of the potato without resistance. Strain the potatoes and set aside. Melt the butter with the parsley in a large sauté pan over a medium heat. Add the potatoes and toss to coat. Season the potatoes to taste with salt and pepper.

Spoon the beef stew onto 4 serving plates and serve the parsley potatoes alongside.