I've made this so often I had to search a while through my cookbooks to see where I originally found it. It is always listed as "Poulet Marengo", in both the NY Times cookbook and From Julia Child's Kitchen . The Times cookbook seems to be the original one I used, as he uses tarragon (which I love, but many people loathe), Julia suggests thyme and oregano and bay for seasoning. The original dish was made by Napoleon's chef in the field after the battle of Marengo, and originally contained crawfish, eggs, and olives, as well as the chicken, tomatoes, and mushrooms. Wherever it came from, it is delicious on a chilly day with a basket of warm French bread.
Lately, I've preferred using chicken thighs in this, bone-in, but you can use a cut up whole chicken if you prefer. I also remove the skin before sauteing if the skin looks fatty - it is tedious to have to spoon off the chicken fat just before serving.
Preheat oven to 350F.
4-6 pieces of chicken thighs (I usually leave the skin on )
1 tablespoon unsalted butter
1 tablespoon good olive oil
Rinse and pat the chicken pieces dry. Heat the butter and oil in a large skillet and sear both sides of the chicken, then remove chicken pieces to an oven proof casserole dish.
Add to the butter and oil left in the skillet:
1 cup dry white wine
1 heaping teaspoon tarragon OR basil, or oregano and thyme
10 sliced white mushrooms
2 cups canned plum tomatoes, with the juice (I cut the whole tomatoes into 3 pieces before adding)
1 medium sliced onion
1 bay leaf
salt and pepper to taste
2 cloves peeled garlic, mashed with the side of a knife
Stir the ingredients in the saute pan until hot, then pour over the chicken pieces, and place in oven, covered with foil, for an hour to an hour and a half. Larger pieces take a little longer. Serve with a nice loaf of bread and unsalted butter, or a side of rice or noodles.