Preheat oven to 300 degrees F.

Pat dry chuck roast. Season on both sides generously with Kosher salt and ground black pepper.

In a large Dutch oven, heat a few generous drizzles of oil over medium-high heat. Once hot, sear chuck roast on both sides until a golden brown crust forms, about 5 minutes per side. Remove from the pot and set aside.

Reduce heat to medium. In the same pot, melt the butter. Add the sliced onions and cook, stirring occasionally, for 25-30 minutes.

Add minced garlic for another 2 minutes. Stir in the white wine to deglaze, then let it reduce by about half. Sprinkle flour and stir to coat.

Add beef broth, Worcestershire sauce, bay leaves, and sprigs of rosemary and thyme. Bring to a simmer. Season with salt and pepper to taste.

Return the seared chuck roast into the pot, ensuring the liquid covers about ¾ or more of the beef. If not, top with more broth.

Cover tightly with the lid and braise in the preheated oven for 3.5 hours until tender. If desired, cook for an additional 20 minutes.

Remove from the oven. Increase oven temperature to 400 degrees F.

In the same pot, shred the beef into smaller chunks and discard excess fat, bay leaves, and herb bundles.

Top evenly with shredded Gruyere cheese. Return to the oven until the cheese is melted, about 5-7 minutes.

Serve warm over mashed potatoes or with toasted baguette slices.