In a large pot, heat the olive oil over medium-high heat. Season the chuck stew meat with 1 teaspoon of kosher salt and black pepper, then brown the meat on all sides.
Once browned, remove the meat from the pot and set it aside. In the same pot, melt the butter and add the sliced onions. Cook the onions until they are caramelized, stirring occasionally.
Add the minced garlic to the onions and cook for an additional minute. Sprinkle the flour over the mixture and stir well to combine.
Pour in the Worcestershire sauce, Dijon mustard, and dried thyme, mixing everything together. Then, return the browned meat to the pot.
Add the beef broth and bay leaf, bringing the mixture to a simmer. Cover the pot and let it cook for about 1.5 to 2 hours, or until the meat is tender.
Once the meat is tender, stir in the dry orzo and cook for an additional 10-12 minutes, or until the orzo is al dente. If the mixture becomes too thick, add more beef broth as needed.
Finally, remove the bay leaf and stir in the shredded Swiss cheese until melted and well combined.
