6 cups chicken stock
2 stalks celery, coarsely chopped
6 to 8 stems fresh tarragon
2 bay leaves, torn
2 garlic cloves, peeled and crushed
1 tsp. whole black peppercorns
1½ lb. skinned boneless chicken breasts (about 4 breasts)
10 Tbsp. unsalted butter, divided
1 cup fresh cider, warmed and divided
10 oz. cored Granny Smith apples (about 2 apples), diced into 1/3-inch cubes (about 2½ cups)
2 cups thinly sliced leeks, washed well
4 cups trimmed and quartered small white button mushrooms
6 Tbsp. all-purpose flour
¼ cup Calvados apple brandy
¼ cup heavy cream, at room temperature
Salt and freshly ground black pepper to taste
1½ Tbsp. finely chopped fresh tarragon leaves
• Combine the chicken stock, celery, tarragon, bay leaves, garlic and peppercorns in a large (6- to 7-quart) stockpot. Bring the mixture to a boil over medium-high heat. Reduce the heat to medium and let the broth simmer 5 to 10 minutes to give the flavors a chance to meld.
• Lightly salt the chicken breasts and add them to the simmering broth, taking care to fully submerge them in the liquid. Cook the breasts, uncovered, turning them occasionally to make sure they cook evenly.
• After about 10 minutes, start checking the chicken for doneness by sticking a knife into the thickest part of each breast. If there is any sign of pinkness, allow the breast to continue cooking. (Total cooking time can vary considerably depending on the size and thickness of the breast.) Once the breasts are cooked through, remove them from the stock and set aside. Strain the vegetables and herbs out of the stock and reserve 2 cups of the liquid. Clean out the pot.
• Melt 2 tablespoons butter in the pot over medium-high heat. Add 1/2 cup cider and bring to a simmer. Add the apples and cook until they are tender but not mushy, no longer than 5 minutes. Stir regularly to ensure even cooking. Transfer the apples and any liquid to a small bowl and set aside.
• Add another 2 tablespoons butter and melt over medium to medium-high heat. Add the leeks and sauté them about 10 minutes. Add the mushrooms and continue to cook, stirring regularly, until the mushrooms have exuded all of their moisture, about 8 to 10 more minutes. Meanwhile, chop the reserved chicken into bite-size pieces. Combine the cooked leeks and mushrooms with the reserved apples and clean out the pot again.
• Add the remaining 6 tablespoons butter and melt over medium heat. Remove the pan from the heat and add the flour to create a roux. Return the pan to medium heat and cook the roux for 2 to 3 minutes, whisking regularly. Gradually add the reserved 2 cups stock, the remaining 1/2 cup cider and the Calvados, whisking constantly to prevent lumps. Bring the mixture to a boil and allow it to boil just a few minutes, until thickened. Immediately reduce the heat to low.
• Add the chicken pieces along with the cream and the apples, leeks and mushrooms. Stir gently to combine. Cook a few more minutes to heat through and allow the flavors to meld.
• Season to taste with salt and black pepper. Stir in the chopped tarragon and serve immediately as is, or over my favorite: a generous helping of garlic mashed potatoes.