Preheat oven to 325°. Sprinkle short ribs with 1/2 teaspoon pepper and salt. In an ovenproof Dutch oven over medium-high heat, brown ribs in oil in batches. Remove meat and set aside. Add next five ingredients to drippings; cook until tender. Add wine, stirring to loosen browned bits from pan. Bring to a boil; cook until liquid is reduced by half.
Return ribs to pan. Add 4 cups broth, rosemary, oregano, bay leaf and remaining pepper; bring to a boil. Bake, covered, until meat is tender, 1-1/2 to 2 hours. Remove ribs to a serving platter and tent with foil. Discard herbs.
Pour drippings and loosened browned bits from roasting pan into a measuring cup. Skim fat. Add enough remaining broth to drippings to measure 1 cup. In a small saucepan, melt butter; stir in flour until smooth. Gradually whisk in broth mixture. Bring to a boil, stirring constantly; cook and stir until thickened, 1-2 minutes. Serve with ribs.