Preheat oven to 375 degrees.
Heat oil in a sauté pan. Season chicken with salt and pepper on both sides. Place into pan and brown both sides, about 3-5 minutes per side.
Transfer chicken to a baking dish (I used aPyrex dish). Add lemon juice, chicken stock, and garlic. Place the lemon slices on top of the chicken (this will help flavor and keep moisture in the chicken!). Top with rosemary sprigs and place into the oven for 45-60 minutes or until cooked all the way through.