Position rack in center of oven and preheat to 400°F In a small bowl, mix 2 tbsp of cider, 1 tbsp of mustard,1 tbsp of the tarragon, 2 tsp of the parsley, the butter, salt and pepper.
Scatter the carrots fennel and onion over the bottom of a 10 x 15 baking dish. Arrange chicken pieces on top of the vegetables. Brush the cider mustard vinegar mixture over the chicken and roast for about 30 minute.
In a small bowl mix remaining 1/2 cup cider, 1 tbsp mustard, creme fraiche, and the cornstarch. Whisk in the chicken broth, vinegar and salt.
Remove pan from the oven and reduce the temperature to 375°F Pour the creme fraiche mixture over the chicken then scatter the apples around. Return the pan to the oven and roast until the vegetable and apples are tender and the chicken is done, about 20 - 30 minute.
Transfer the chicken to a warm platter. Use a slotted spoon to arrange the vegetables and apples around the chicken. Sprinkle with a little salt and the remaining tarragon and parsley. Tilt the pan so that the juices gather in one corner. Skim as much fat as possible from the pan. Seadon the sauce to taste and pour into a pitcher to pass at the table,.