Drizzle the chicken with olive oil then season generously with salt and pepper all over.
Make sure to season the cavity of the chicken as well.
Place lemon slices and thyme inside the cavity of the chicken and sprinkle thyme leaves over the chicken.
Slice the lemons and the tops off of the garlic bulbs. Place them in a roasting dish then place the chicken on top.
Pour the chicken stock around the chicken then cover with foil.
Place in the preheated oven and roast for 30 minutes then remove the foil and roast for another 15-30 minutes or until the chicken is golden brown and cooked through.
Allow the chicken to rest for at least 10 minutes then slice and serve, drizzled with the pan juices.