½ to ⅔cupmaple orange saucethe fresh and unused sauce
Coarse sea salt and pepperto taste
A day before:
Spatchcock the chicken and season it all over - front, back, and underneath the skin - with salt, pepper, garlic, and onion powder.
Make a jar of the maple orange sauce. Mix well.
Place the chicken breast side in a casserole or baking dish that has just enough room to fit one bird snuggly. Pour-in half a cup (½ cup) of the sauce and cover and marinate the chicken overnight in the fridge. Store the rest of the fresh sauce for gravy use.
On the day
Remove the chicken from the fridge 30 minutes before roasting. Preheat the oven to 400°F (204-205°C) convection oven or 425°F (218°C) regular oven (without the fan).
Line a sheet pan with parchment and add the sliced orange and lemon, and quartered red onion.
Place a wire rack over the sheet pan and place the chicken breast side up on top of the sheet. Brush the chicken with the marinade we used to marinate the chicken a night before and save the rest of the marinade for the next step.
Roast for 30 minutes. Remove the sheet pan, pour over the remainder of the marinade, and cover up the parts that brown too fast with foil paper. Rotate the sheet and send the chicken back to roast for 20 more minutes.
The chicken is cooked through when a meat thermometer registers 165°F (74°C) for the breast meat and 175°F (79-80°C) for the thighs. (Note: the chicken continues to cook up a few degrees right after you remove it from the oven. In general, it should come up another 2-3 degrees).
To make the gravy:
Rest the chicken for 15 minutes before carving. Use this time to make the gravy.
In a saucepan over medium-low heat, add 2 tbsp dripping from the sheet pan. Whisk in flour until fragrant (1 to 2 minutes). Slowly whisk in the remainder of the maple orange sauce (i.e. the fresh and unused sauce) and chicken stock. Bring it to a simmer, stir-often and cook until thick enough to coat the back of a spoon, about 4-5 minutes. Season with salt and pepper to taste. Strain through a fine-mesh sieve into a gravy boat.
Remove the legs then remove the entire chicken breasts. Carve the breast at a 45 degree angle against the grain so the meat remains tender. Decorate the chicken with roasted citrus fruits and red onions from the sheet pan and serve the gravy boat on the side.