4 boneless, skinless chicken breasts (about 1½ pounds), butterflied (note: placing chicken breasts in the freezer for 10-15 minutes will make butterflying easier)
Kosher salt and black pepper
All-purpose flour, for dredging
6 tablespoons unsalted butter
3 tablespoons extra-virgin olive oil, plus more as needed
1 shallot, peeled and sliced lengthwise
1 lemon, halved (half thinly sliced and seeds removed; half juiced, about 2 tablespoons)
3/4 cup chicken stock
4 teaspoons drained capers
Coarsely chopped fresh parsley, for garnish (optional)

4 boneless, skinless chicken breasts (about 1½ pounds), butterflied (note: placing chicken breasts in the freezer for 10-15 minutes will make butterflying easier) 6 tablespoons unsalted butter 3 tablespoons extra-virgin olive oil, plus more as needed 1 shallot, peeled and sliced lengthwise 1 lemon, halved (half thinly sliced and seeds removed; half juiced, about 2 tablespoons) 3/4 cup chicken stock 4 teaspoons drained capers

1. Season both sides of the chicken with salt and pepper. Dredge the chicken in flour and shake off any excess.
2. In a large skillet, heat 3 tablespoons butter and the olive oil over medium-high heat until the butter has melted. Working in batches to avoid crowding the pan, add the chicken and sauté until golden brown and cooked through, about 3 minutes per side.
3. Remove the chicken, place on a plate and repeat with the remaining pieces, adding more olive oil if needed.
4. Once the chicken is cooked, add the shallot and lemon slices to the pan and sauté, stirring occasionally, until lightly caramelized and fragrant, 2 to 3 minutes. Add the stock and simmer until reduced by half, about 3 minutes.
5. Reduce the heat to low, then stir in the remaining 3 tablespoons butter, capers and lemon juice, to taste. Season with salt and pepper to taste. Serve the chicken with the sauce poured over the top. Garnish with parsley if desired.