Season chicken pieces on both sides with salt and pepper and grill. Remove chicken to a baking sheet and bake in the oven for 20 minutes at 350°F

Add olive oil and mushrooms in a stockpot, season with salt and pepper and sauté until golden brown. Add the shallots and cook for 30 seconds. Add the Cognac and cook until completely reduced, then add the wine, and cook until completely reduced. Add the stock and tomato and bring to a simmer. Cook until the sauce is thick enough to coat the back of a spoon and then swirl in the butter.

Once the butter is added, the sauce can't be further reduced because it will break. Season with salt and pepper and stir in the tarragon and parsley

Remove the chicken from the oven and let it rest for 5 minutes. Add any juice from the chicken to the sauce. Plate and top with sauce