Preheat an oven to 350 degrees F. Pat the beef very dry using a paper towel and generously season on all sides with salt and pepper.

In a large braiser or dutch oven, heat oil until over medium-high shimmering. Brown meat on all sides until deeply golden brown, 3-4 minutes per side. Transfer to a plate.

Reduce heat to medium-low and add onions, leeks, and garlic. Saute until onions and leeks are just tender, about 5 minutes.

Add the wine and stock and bring to a simmer. Season lightly with salt and pepper. Return the meat to the pan and nestle in the carrots, thyme sprigs, and bay leaves. The meat should sit just above the liquid line. For a good braise, you don't want it fully immersed in the liquid. Cover and transfer to the oven for 2 1/2 hours. Remove lid and cook for another 30-45 minutes, until the beef is fork-tender.

Remove from the oven and skim off the layer of fat on top and discard. Cover and rest the beef in the juices for at least 45 minutes. Gently re-warm on the stove before serving.