Preheat oven to 425 F.
Warm all of the beef broth in a pot over low heat.
Heat 1/2 cup of the oil in a large Dutch oven over medium heat.
Sprinkle the oil with flour and whisk continuously, 15-20 minutes or until the roux has turned the color of chocolate.
Slowly whisk in 6 cups of beef broth. Bring to a boil then reduce to a simmer and let simmer 5 minutes.
Strain roux through a wire-mesh strainer and reserve.
Wipe out the Dutch oven. Add remaining 1/2 cup of oil over medium-high heat.
Working in batches, sprinkle chuck with Creole seasoning and sear until brown. Remove to a bowl or large plate.
Add the onions to the Dutch oven along with 1 cup of water. Saute 12 minutes, stirring often.
Add the pepper, celery and garlic.Saute 5 minutes.
Add the tomato paste and hot sauce, if desired, and saute 3 minutes.
Add remaining 2 cups of beef broth and stir, simmering, for 5 minutes.
Add meat to pot.
Add the roux mixture.
Stir gently. Add water, if needed, to completely cover the meat.
Cover the Dutch oven and bake for 20 minutes. Note: If your Dutch oven lid doesn't fit tightly, cover the pot with a piece of aluminum foil and then add the lid.
Reduce heat to 200 F and bake for 8 hours.
Remove from oven. Skim off any fat on the top.
Remove beef to a cutting board, let cool slightly, and shred.
Bring gravy mixture to a boil and simmer for 20 minutes, stirring often, until thickened.
Add the meat back along with the green onions.
Stir and serve.