Chop the onion and garlic finely. Place 1 cup of flour into a bowl. Smooth out all lumps with a knife. In a Dutch oven (over medium-high heat), pour 1 cup of oil in. Allow the oil to come up to heat. Carefully sprinkle the flour into the oil, while whisking constantly - from this point on - with a wire whip. For the roux to achieve a dark chocolate brown color, it will take about 6-8 minutes of whisking.
Carefully place the onions into the roux, add a little salt and saute until the onions are clear. Pour the hot roux and onions into a large pot over a low flame.
In stages, add 1 quart of water to the skillet. Bring the liquid to boiling. Pour the hot water into the roux. Break it down with fast whisking. Repeat adding water to the skillet, boiling it and pouring it into the pot until the desired consistency - relatively thin - has been reached. (Heating the liquid is necessary to prevent the roux from becoming a sludge-like mess.) Pour the wine into the skillet, heat and pour it into the pot. Add the garlic, Tabasco, Worcestershire and salt to the pot. Bring the contents of the pot up to a rolling boil, reduce the heat and throw the ribs in.
Simmer the gumbo, uncovered, until the ribs are super-tender - about 1 - 1 1/2 hours. Periodically, skim off any grease or scum rising to the surface. Near the end of the cooking time, correct for seasoning.
Serve the ribs (one rib per bowl) in large, wide bowls over rice. Ladle the gumbo liquor over the rice.