To spatchcock the chicken, you cut out the backbone of the chicken with poultry shears, cutting along both sides, and then press down on the breastbone with the palm of your hand until the chicken lies flat.
1 4 pound whole chicken
Heat the oven to 425°F.
in a large bowl, combine the seasonings.
Juice from one lemon, 1/4 cup whole grain Dijon mustard , 3/4 cup olive oil, 1 teaspoon fresh rosemary, 1 tablespoon fresh thyme, salt
Toss the onions and potatoes in the seasoning mixture.
2 yellow , 2 pounds russet potatoes
Spread them out over a sheet pan, leaving room in the middle of the pan the pan.
Place the spatchcocked in the middle of the pan and rub it with the butter and sprinkle with salt and pepper.
3 tablespoons butter
Roast the chicken and potatoes for about 40 minutes, until the chicken reaches 165 degrees F.
Remove the pan from the oven and tent the chicken for 10 minutes.
Cut the chicken into pieces and serve with the potatoes.