Remove the chicken to a platter or dish when nicely browned and brown the remaining pieces the same way. When all the chicken is browned and on a platter, pour over the Cognac, brandy or rum, and set aside.
Meanwhile, add a little more oil to the pan if needed, and stir in the mushrooms, garlic, thyme, and the reserved onions and bay leaf. Sauté the vegetables for 5 to 6 minutes, or until lightly browned, stirring a couple times.
Then sprinkle the vegetables with flour and cook over low heat stirring for 2 to 3 minutes longer. Stir in the tomato paste, and mix well.
Pour in the wine and chicken broth, stirring until the sauce is well blended. Return the chicken with Cognac drippings to the skillet or pot, stirring well, and bring the gravy to a gentle boil, turning over the chicken several times.
As soon as the gravy is bubbling, cover the skillet or pot and reduce the heat to medium-low. Simmer the chicken for 35 to 40 minutes or until the pieces are fork tender and the juices run golden when pierced with a fork, turning over occasionally.
At serving, place the chicken in a warm serving dish and set aside. Bring the sauce to a boil again, and cook for a few minutes, stirring until the gravy is the consistency of heavy cream. Pour the wine sauce over the chicken and serve immediately.