Preheat oven to 425 degrees
Sprinkle the chuck roast with salt and pepper and dust with flour, covering the entire pot roast.
Heat a Dutch oven over medium high heat. When the pan is hot, add the oil. When the oil starts to shimmer, add the roast. The oil should be hot enough that the meat sizzles when it hits the pan.
Brown the roast on two sides. About 5 minutes per side.
Place the seared roast beef in the roasting pan uncovered. Cook the roast at 425 degrees for 20 minutes.
Lower oven temperature to 325 degrees.
Add the water or broth and sprinkle the vegetables around the meat.
Cover and oven roast for 2 ½ to 3 hours or until meat is fall apart tender. Check the meat about half way through cooking time to see if more water needs to be added. Add up to one to 1 ½ cups.
Use a meat fork and large spoon to remove the pot roast and the vegetables to a serving platter. Cover with foil to keep warm.
Pour the drippings/liquid from the roasting pan into a Pyrex measuring cup. Add enough beef broth or water to equal two cups of liquid. Many times, my Le Creuset Dutch Oven is so heavy duty that there's no liquid left at the end of the cooking time. Use one 14.5 ounce can of beef broth and add a little water to make 2 cups.
Heat the Dutch oven over medium heat stove top. Add the butter to the Dutch oven. Once the butter is melted, add the flour and stir over medium low heat making a roux.
To serve, simply transfer roast to a serving platter and arrange vegetables around the roast. Serve the gravy in a gravy boat on the side.
Cook for about 3 minutes to cook the raw flour flavor out of the roux, stirring to dislodge any brown bits that have stuck to the bottom. That's what makes a better gravy. Watch it closely so it doesn't burn. Add the beef stock and Worcestershire and and stir until thickened. Taste and adjust for salt and pepper.