Step 1

Make the chicken cutlets: Lay the chicken breast on a cutting board. Hold it flat with the palm of your hand. Use a long, sharp, non-serrated knife like a long, thin slicing knife, or a chef’s knife. Slice the chicken in half horizontally, as smoothly as you can, and in as few slices as possible, starting at the thickest side. You will end up with 2 chicken cutlets. Repeat with the remaining chicken breasts. Layer each cutlet one at a time between two sheets of wax paper or plastic wrap. Gently use the smooth side of a meat pounder to shape the cutlet into an even 1/2-inch thickness. Depending on the thickness of the cutlets you can also skip this step, if you like.

Step 2

Season the chicken: Lightly season the chicken cutlets all over with salt and pepper.

Step 3

Pan fry the cutlets in batches: Heat 1 tablespoon olive oil in a large skillet over medium-high heat. When the oil is hot, add half of the cutlets. Cook until golden brown on both sides, about 4 minutes per side. Transfer the cutlets to a large plate and cover with an overturned bowl to keep warm. Add the remaining olive oil to the pan and repeat with the remaining cutlets. Set them aside with the first batch.

Step 4

Deglaze the pan: Add the shallots, wine, and water to the skillet. Raise heat to high and cook, scraping the bottom of the pan with a wooden spoon or spatula to release all the browned bits of chicken. Continue cooking, stirring constantly, until the liquid has reduced by half, about 3 minutes.

Step 5

Finish the pan sauce: Add the mustard and pour any accumulated chicken juices from the plate into the sauce. Continue simmering over low heat, using a whisk or fork to incorporate the mustard. Cook until the sauce is completely emulsified and thickened but still pourable. If it’s too thick for your liking, add a few tablespoons of water. If it’s not thick enough, continue cooking until it reaches the desired consistency. Remove the pan from the heat and stir in the tarragon. Season with salt and pepper to taste.

Step 6

Plate chicken and drizzle with sauce: If you like, cut the chicken into slices (or leave whole),  then divide chicken among plates. Drizzle the sauce over the chicken and serve immediately.