With a velvety smooth sauce, this Stroganoff gets its complex flavor from Dijon mustard, fresh tarragon, sour cream, and Marsala wine, which adds just a touch of rich sweetness. I use chicken thighs here because they’re juicier and less expensive than breasts. Serve with steamed rice, brown rice or buttered noodles. Although Marsala hails from Sicily, my Greek family insists that both the port of Marsala and the wine are named after a Greek warlord who believed his soldiers fought better when they’d been fortified with a little Italian vino.
1. Cut the chicken into 1-inch chunks. Sprinkle with the salt and pepper. Heat the oil in a large saucepan over medium heat until it is shimmering but not smoking. Add the shallots and cook, stirring, until they’re a light golden color, about 3 minutes. Turn the heat to medium-high, add the chicken pieces, and cook, stirring, until golden on the outside and almost cooked through, about 5 minutes. Transfer the chicken and the shallots to a plate.
2. Deglaze the pan by turning the heat to high, pouring in the Marsala, and scraping up all the browned bits from the bottom of the pan with a wooden spoon. Boil until the liquid is reduced by half, about 1 minute. Add the chicken stock, stir, and boil until the liquid begins to look syrupy, about 2 minutes. Reduce the heat and pour any juices that have accumulated on the plate underneath the chicken back into the pan. Add the mustard and the minced tarragon and simmer for 3 minutes. Turn off the heat and whisk in the sour cream, stirring until smooth. Turn the heat to low, taste, and add more salt and pepper if necessary.
3. Add the chicken and shallots to the pan and gently heat over low heat until the stroganoff is warmed through; do not let it boil. Serve over noodles or rice and garnish each serving with a tarragon sprig.