De-bone chicken and tear meat into large, bite-size pieces. Place chicken carcass and skin in a medium saucepan and add 4 1/2 cups of water. Bring to a boil over high heat, reduce heat to a simmer and cook for 30 minutes. Strain mixture through a fine sieve. Discard solids and reserve stock; you should have about 3 1/2 cups. If not, add enough water to bring level up to 3 1/2 cups.
Heat a large skillet over medium high heat. Add bacon and cook until crisp, 4 to 6 minutes. Remove bacon and set aside on paper towels to drain. Add the butter to the rendered bacon fat in the skillet and, when melted, add the mushrooms. Cook, stirring occasionally, until mushrooms are soft and lightly golden around the edges, about 4 minutes. Add the onion, salt and pepper and cook until the onions are wilted, about 2 minutes. Add the flour and continue to cook, stirring, until flour is a medium brown color, slightly darker than peanut butter. Add the stock and thyme and cook, stirring occasionally, until sauce is thickened and smooth, 10 to 15 minutes. Add the tomatoes and cook until they release their liquid and begin to break down slightly and the sauce is a nice consistency, 10 to 15 minutes. Add the chicken pieces and cook just until warmed through, 5 to 10 minutes. Stir in the parsley and serve ladled over split hot biscuits. Garnish with thinly sliced scallions, if desired.
Yield: 6 to 8 servings