Heat oven to 350˚F.

In a large pan set over medium heat, heat the oil. Add the steak and cook, turning the pieces until well browned on all sides, about 5 minutes. Transfer the steak to a 2 1/2 quart baking dish.

Stir the flour into the pan drippings. Cook, stirring contantly until dark brown, about 2  minutes. Add the celery and onion, reduce the heat to medium and cook until the vegetables are tender, about 5 minutes.

Stir in the broth, red pepper flakes, Worcestershire sauce and wine. Bring mixture to a boil. Pour the hot mixture over the steak in the baking dish. Cover with foil and bake for 1 hour.

Add the bell peppers and continue to bake, uncovered, for 30 minutes or until steak is fork tender. Baste the steak with the sauce as it cooks.

Serve hot right from baking dish. May be served over a bed of rice or a side of mashed potatoes goes well with the gravy.