In a large skillet with high sides, heat the oil, 3 turns of the pan, over medium-high heat. Season chicken with salt and pepper liberally. When oil ripples, add chicken and brown it on both sides, 7 to 8 minutes total. Add balsamic vinegar and stir 30 seconds, add stock, apricots and thyme and reduce heat to medium-low to low. Place a lid on the pan and simmer 10 minutes. Take lid off, stir in the parsley, chives, lemon zest and juice and turn off heat. Let stand a couple of minutes, remove the thyme sprigs and serve.