Slice 2-3 large sweet or yellow onions into thin strips. In a large skillet, melt 2 tablespoons of butter over medium heat. Add the onions, stirring occasionally for about 15-20 minutes until they become deeply caramelized and golden.

Season a 3-4 pound beef chuck roast generously with salt and pepper. In a large Dutch oven, heat 1 tablespoon of olive oil over medium-high heat. Sear the roast on all sides for about 3-4 minutes until it develops a nice brown crust.

Remove the seared beef from the Dutch oven. In the same pot, add the caramelized onions and 4 cloves of minced garlic, stirring for another minute. Pour in 1 cup of red wine or more beef broth, scraping up any brown bits.

Return the beef to the pot, add 2 cups of beef broth, 2 sprigs of fresh thyme, and 2 bay leaves. Bring the mixture to a gentle simmer.

Cover the Dutch oven and transfer it to a preheated oven at 300°F (150°C). Let it braise for about 3-4 hours, or until the beef is fork-tender.

Once done, remove it from the oven and let it rest for a few minutes. Discard the bay leaves and thyme stems. If desired, shred the beef into chunks and sprinkle with grated Gruyère cheese.

Plate the pot roast with onion-flavored broth poured over the top and garnish with fresh parsley.