Halve the chicken pieces horizontally with a sharp knife and flatten them slightly between sheets of plastic wrap. Dredge lightly in flour, shake off the excess and put on rack to dry.

In a large heavy skillet heat 1 tablespoon of the butter and the oil over moderately high heat until the foam subsides and in the fat saute the chicken pieces, seasoned with salt and pepper, for 1 minute on each side, or until they are cooked through. Transfer a 350 degree oven to keep warm, covered loosely.

Pour off the fat in the skillet, to the skillet add the remaining 1 tablespoon butter, the wine, the chicken stock and the lemon juice, and bring the mixture to a boil. Stir in the capers, the parsley, and salt and pepper to taste and spoon the sauce over the chicken.