Mustard Chicken

0 Preheat the oven to 375F.
1 In a large skillet, heat the olive oil over medium heat.  
2 Season the chicken with salt and pepper, then add it to the skillet.  Brown it evenly on all sides for about 15 minutes.  Transfer to a plate and set aside.
3 Add the shallots to the pan and cook, stirring occasionally, until soft.  Add the garlic and cook for another minute.  
4 Add the chicken broth, mustard, and wine and bring to a boil.  Return the chicken with all the juices to the pan, cover with a well-fitted lid, and transfer to the hot oven.
5 Bake for about 45 minutes, or until the chicken reaches an internal temperature of at least 165°F in the thickest part, away from the bone.
6 Transfer the chicken to a serving platter and cover to keep warm. Return the pan to the stove top, add half of the chopped tarragon and the crème fraiche, and simmer until the mixture thickens.
7 Spoon sauce over chicken and garnish with the remaining tarragon.