Chicken Marengo

I obtained the following recipe from the owner and chef at a small restaurant in Paris. Although she took offense when I questioned the historical accuracy of the ingredients, her version of Chicken Marengo is very tasty. It may not have been what was served to Napoleon after his victory against the Austrians, but I have no doubt that he would have preferred it had he been given the choice.

Cut a small roasting chicken (around 3 pounds) into pieces
Heat 3 tbs. of olive oil and 2 of butter in an earthen casserole or heavy Dutch oven, and sauté the chicken until golden brown on all sides
Add 1 tsp. chopped shallots, salt, pepper, 1 tsp. dried tarragon, 1 clove finely chopped garlic, 1 cup dry white wine and cook until wine is reduced by half
Add 2 tbs. tomato paste and 1 cup of chicken bouillon or liquid from cooking 1/2 lb. mushrooms in salted water, reserving mushrooms to add later
When chicken is tender, place pieces on a heated platter. Reduce sauce and stir in 1 tbs. flour blended with 1 of butter. Put mushrooms on the chicken, strain sauce over it, garnish with parsley, and serve hot
To satisfy Napoleonic tradition, garnish with crayfish (cooked, presumably)
To satisfy the lady from Lyon, surround the chicken with deep-fried eggs