Prepare Champignons Sautés au Beurre per the recipe here.
Get all of the remaining ingredients prepared per the amounts above (mis en place).
Heat the dutch oven to medium add butter, and when hot, sauté the bacon slowly until it is very lightly browned. Remove to a side dish and cover.
Dry the chicken thoroughly and brown it in the hot fat in the casserole adding more butter if needed. Work in in batches if needed, so as not to crowd the pan. Keep the browned chicken warm while cooking the rest.
Season the chicken. Return the bacon to the casserole with the chicken. Cover and cook slowly for 3 minutes, just to warm up the bacon and let flavors meld a tad.
Uncover, and pour in the cognac. Averting your face, ignite the cognac with a long lighter or lighted match. Shake the casserole back and forth for several seconds until the flames subside.
Pour the wine into the casserole. Stir in the tomato paste, garlic, and herbs. Add just enough stock or bouillon to cover the chicken. Bring to a simmer. Cover and simmer slowly for 20-30 minutes, or until the chicken is tender and its juices run a clear yellow when the meat is pricked with a fork (depends on cuts used). When fully cooked, remove the chicken to a side dish and keep covered. .
Simmer the remaining cooking liquid in the casserole for a minute or two, skimming off fat. Then raise heat and boil rapidly, reducing the liquid to about 2¼ cups. Correct the salt and pepper seasoning, remove from heat, and discard the bay leaves.
Meanwhile, make a bit of a roux in a small fry pan. Heat it up, melt the butter, and blend the flour into it, mixing it into a smooth paste (beurre manie). Beat the paste into the hot liquid with a wire whip. Bring this to the simmer, stirring, and simmer for a minute or two. The sauce should be thick enough to coat a spoon lightly.
Add the chicken back into the pot, along with the mushrooms and onions, and baste with the sauce. If the dish is not to be served immediately, film the top of the sauce with stock or dot with small pieces of butter. Set aside uncovered. It can now wait indefinitely.
Shortly before serving, gently bring the coq au vin to the simmer, basting the chicken with the sauce. Cover and simmer slowly for a few minutes, until the chicken is warmed through.
Serve from the casserole, or arrange on a hot platter. Serve with Parsley Potatoes and hot buttered peas, and decorate with sprigs of parsley.
Notes
* Recipe calls for "lean bacon," but I had read that bacon we find in the US is too salty and sometimes smoky. I didn't simmer the pork belly this time, but last time I did (for beef bourguignon). I'm not sure it makes a difference.... ** Apparently a frying chicken means a whole older chicken that might be tougher, and therefore be up for longer cooking time (as a coq/rooster would be). Cooking on the bone would also allow more cooking time. This time I cut up strips of thighs (~3/4" x 3/4 " x 4") and yes, it was a tad too cooked for my taste but no one else thought so.