PLACE THE CHICKEN IN A DUTCH OVEN. SALT AND PEPPER. PEEL AND LIGHTLY CRUSH GARLIC CLOVES AND ADD TO THE POT ALONG WITH THE THYME AND BAY LEAVES. POUR IN ENOUGH RED WINE TO COVER THE CHICKEN LEGS.
PLACE IN THE FRIDGE OVERNIGHT OR FOR AT LEAST 4 HOURS AT ROOM TEMPERATURE.
REMOVE THE LEGS TO A PLATE. STRAIN THE WINE INTO A BOWL. KEEP THE THYME SPRIGS AND BAY LEAVES. RINSE AND DRY THE POT.
CUT THE BACON INTO LARDONS, ABOUT AN INCH LONG AND 1/2 INCH WIDE. ADD A SPLASH OF OLIVE OIL TO THE DUTCH OVEN OR ANY LARGE, STEEP-SIDED PAN WITH A LID. COOK OVER MEDIUM-LOW HEAT UNTIL THE LARDONS ARE BROWNED BUT NOT CRISP. REMOVE TO A BOWL WITH A SLOTTED SPOON.
THOROUGHLY DRY THE CHICKEN LEGS WITH PAPER TOWELS. BROWN, SKIN SIDE DOWN FIRST, ABOUT 4 MINUTES ON EACH SIDE.
MEANWHILE, PEEL THE ONION, CARROTS AND CELERY. CUT INTO 1/2-INCH DICE.
ONCE THE LEGS HAVE BROWNED, REMOVE TO A PLATE. POUR OFF MOST OF THE FAT, LEAVING ABOUT 4 TBSPS.
LOWER THE HEAT AND ADD THE DICED VEGETABLES. COVER AND SWEAT FOR A FEW MINUTES. ROUGHLY CHOP THE GARLIC AND ADD TO THE POT. COOK, STIRRING ANOTHER MINUTE.
STIR IN 1 TSP OF TOMATO PASTE AND 1 TBSP OF FLOUR AND COOK ANOTHER MINUTE.
PUT THE CHICKEN BACK IN THE POT AND HALF THE RESERVED LARDONS.
TIE THE THYME SPRIGS AND BAY LEAVES TOGETHER WITH COTTON STRING. PLACE IN THE POT.
POUR IN 2 TBSPS OF COGNAC OR ARMAGNAC. RAISE THE HEAT TO MEDIUM AND IGNITE WITH A MATCH (WATCH YOUR EYEBROWS!). WHEN THE ALCOHOL BURNS OFF, POUR IN THE RESERVED WINE MARINADE, THYME AND BAY LEAVES. BRING TO A BOIL, REDUCE TO A SIMMER. SKIM OFF ANY FOAM FROM THE SURFACE.
COVER AND SIMMER ON A LOW FLAME OR A 325º OVEN FOR ABOUT AN HOUR. IF THE MARINADE DOESN'T COMPLETELY COVER THE CHICKEN, TURN PIECES HALFWAY THROUGH THE COOKING.
NOTE: ONIONS AND MUSHROOMS ARE ADDED 10 MINUTES BEFORE THE END. SEE BELOW.
MEANWHILE, USING A VERY SHARP KNIFE, TRIM BOTH ENDS OF THE ONIONS.
BRING A POT OF WATER TO A BOIL. DUMP IN THE ONIONS. WHEN THEY RETURN TO THE BOIL, COOK ANOTHER 30 SECONDS. DRAIN AND DUMP INTO A SINK FULL OR A LARGE BOWL OF COLD WATER. SQUEEZE THE ONIONS OUT OF THEIR SKINS AND LAY ON KITCHEN TOWEL.
CUT THE MUSHROOMS LENGTHWISE IN HALF OR QUARTERS DEPENDING ON THEIR SIZE.
IN A FRYING PAN LARGE ENOUGH TO ACCOMMODATE THE ONIONS IN ONE LAYER, MELT 2 TBSPS OF BUTTER AND A SPLASH OF VEGETABLE OIL. ADD THE ONIONS. SALT AND PEPPER. SPRINKLE WITH 1 TSP OF SUGAR. SAUTÉ ON HIGH HEAT, SHAKING THE PAN SO THE ONIONS ROLL AROUND AND BROWN LIGHTLY ON ALL SIDES. ADD TO THE CHICKEN.
ADD ANOTHER 2 TBSPS OF BUTTER TO THE PAN. WHEN HOT, TOSS IN THE MUSHROOMS. SALT AND PEPPER. COVER FOR A MINUTE OR SO, SHAKING THE PAN. THE MUSHROOMS SHOULD DISGORGE THEIR MOISTURE. UNCOVER AND COOK ANOTHE MINUTE OR SO TILL THE MUSHROOMS ARE NICELY BROWNED. ADD TO THE CHICKEN.
WHEN THE CHICKEN IS DONE, FISH OUT BAY LEAVES AND THYME STEMS.
SCATTER THE REMAINING LARDONS ON TOP OF THE CHICKEN.
GARNISH WITH CHOPPED PARSLEY.
SERVES 6
