1. Combine the butter, garlic, parsley, and lemon zest in a bowl. Season with salt and pepper. On a piece of plastic wrap, shape into a thick rectangle, then enclose in the plastic wrap. Refrigerate at least 1 hour, until firm.

2. One at a time, pound each breast between two sheets of plastic wrap with a meat pounder to an even thickness. Season the breasts. Cut the butter into 4 equal sticks and place a stick on each chicken breast. Fold in the sides, then roll up the chicken completely around the butter.

3. Roll each chicken packet in flour, then in beaten egg, and finally into the bread crumbs to coat evenly. Take care to keep the chicken closed around the butter.

4. Add enough oil to come halfway up the sides of a large saucepan and heat over high heat to 350°F (180°C). Add the chicken and cook about 5 minutes, until deep golden brown.

5. Transfer the cooked chicken to paper towels and drain briefly. Serve hot.