01 - Place chicken breasts between two sheets of plastic wrap. Pound to an even 1/2-inch thickness using a meat mallet or rolling pin.
02 - Season both sides of each chicken breast with salt and pepper. Dredge lightly in flour, shaking off any excess.
03 - In a large skillet over medium-high heat, heat olive oil and 2 tablespoons butter until sizzling and fragrant.
04 - Add chicken to the hot skillet. Sauté for 3 to 4 minutes per side until golden brown and cooked through. Transfer to a plate and tent loosely with foil to keep warm.
05 - Pour white wine into the same skillet, scraping up browned bits from the bottom with a wooden spoon. Simmer for 1 to 2 minutes until slightly reduced.
06 - Stir in chicken broth, lemon juice, and capers. Simmer for 2 to 3 minutes until sauce thickens slightly.
07 - Return chicken to the skillet and spoon sauce over the top. Simmer for 2 minutes to warm through. Remove from heat and swirl in 1 tablespoon cold butter for richness. Sprinkle with fresh parsley.
08 - Serve immediately, garnished with lemon slices and additional parsley if desired.