Place the chicken in a small dish and drizzle the olive oil over it. Sprinkle on the rosemary, salt and pepper and lay the lemon slices on top.
Cover the dish and let the chicken marinate in the fridge for at least 30 minutes. Can marinate for up to 4 hours.
Preheat the oven to 350. Set an 8x8 baking dish to the side.
Preheat a skillet on medium high heat. Then drain chicken of any extra oil and place chicken in skillet , with the skin side down. You can leave the lemon slices on if you wish.
Sear both sides of the chicken, until they are golden brown (about 4 to 5 minutes on each side). Then place the chicken in the 8x8 baking dish.
Bake for 20 minutes and then test the deepest part of the chicken with a food thermometer. It should read 165. If chicken is not ready, place back in the oven at 3 minute intervals until it is done.
Let chicken rest for 5 minutes before serving.