Preheat the oven to 425 degrees F.
Sprinkle the inside of the chickens liberally with salt and pepper. Stuff each bird with 3 sprigs thyme, 2 cloves garlic, the bay leaf, onion and lemon. As the chickens cook, this will help keep them moist and also flavor the bird from the inside.
Using kitchen twine, tie the legs together of each bird, and then tuck the wing tips underneath each body so it cooks evenly. Place the birds on a roasting rack over a roasting tray then sprinkle them with salt and pepper.
Place in the oven and roast for 15 minutes. Then reduce the temperature to 375 degrees F and cook until an instant-read thermometer inserted into the joint between the leg and thigh registers 165 degrees F, approximately 1 hour more. When the chicken is done, the skin will be crispy and golden and the juices of the chicken will run clear. Remove from the oven and allow to rest for 15 minutes before serving.
This is a great recipe for the week where you can use the shredded chicken meat for salads, sandwiches, pasta dishes, and stews. Then you can also use the roasted chicken carcasses to make chicken stock, or fortify boxed broth for soups.