In large ziploc bag add flour, brown sugar, garlic powder, onion powder, cumin and cayenne. Add short ribs and shake to coat.
In dutch oven or large heavy skillet melt 1-2 tablespoons butter over medium heat. Add short ribs and brown on all sides. Do not overcrowd so you may need to work in batches. Add more butter if necessary.
Remove browned short ribs to plate. Add wine to deglaze the pan. Stir to remove the brown bits from the pan. Add Worcestershire sauce, beef broth, onions, carrots and browned short ribs.
Cover with lid or heavy aluminum foil and place in oven at 325 degrees for 2-2 1/2 hours or until tender.
Remove the meat and veggies to a platter. Thoroughly mix 1 1/2 tablespoons cornstarch with 1 1/2 tablespoons cold water, then pour into your broth mixture.
Cook over medium heat for several minutes to thicken. Season with kosher salt and fresh ground black pepper to taste. Serve gravy poured over meat and veggies.