Season the inside cavity of the chicken with half of your salt and the pepper.
Now place half of your orange and lemon slices, garlic cloves, and herb sprigs in the cavity as well.
Cross the legs one over the other or tie them together with kitchen string to hold the contents inside.
Tuck the wings underneath the chicken.
Now rub your olive oil over the top of chicken and then squeeze some orange and lemon over the the chicken and rub the juice into the skin, then sprinkle the chicken with the remaining 1 teaspoon salt.
Place your chicken, breast side up, in a roasting pan or dutch oven.
Toss in any remaining orange and lemon slices, garlic, ½ cup of chicken stock, potatoes and herb sprigs in the pan.
Roast until the chicken’s juices run clear when a thigh is pierced with a fork or a thermometer registers 160°F (71°C) when inserted into the thickest part of a thigh, 1 ½ to 2 hours, depending on the size.
Transfer the chicken to a cutting board, cover loosely with aluminum foil, and let rest for 10-15 minutes.
scoop out your potatoes on to a plate and cover with aluminum foil to stay warm
While the chicken rests, pour 1 cup of your stock into the roasting pan and with a whisk scrape up any bits from the pan as you mix.
Now pour this mixture into a medium sauce pan over medium high heat.
Reduce your mixture by almost half.
Strain the pan juices through a fine-mesh sieve and pour back into the sauce pan and place over low heat.
Add the butter and any additional chicken stock that is needed and mix until the butter melts.
Squeeze the juice from the orange and lemon halves into the pan and cook, stirring, until the juices have thickened a little more and are glossy, about 5 minutes.
Stir in the chopped thyme.
Taste and adjust the seasoning
Carve the roast chicken. Now add your potatoes to a large platter topped with the chicken
Drizzle a little of your sauce over top and serve with the remaining warm sauce on the side.
Tip:If your chicken is not as golden brown on the outside as you would like when it is done cooking, place it under a broiler on high heat (making sure the chicken does not touch the broiler) until it starts to brown.Remove and let the chicken rest under aluminum foil.