Tarragon and Crème Fraîche Chicken

This is a fairly fancy dish that would be wonderful for a Friday-night dinner party. Just a touch of tangy, thick cream, stirred in at the end, gives the flavorful sauce a rich, velvety consistency (a hit with the immersion blender is essential here to smooth out and emulsify the sauce, which will have separated during the day). Spoon it over a mixture of wild rice and brown rice scented with orange and cranberries, and perhaps toss a few cold-weather lettuces in lemon juice and olive oil t