1 (3-3½ pound) whole chicken
Kosher salt and freshly ground black pepper
1½ pounds small potatoes, halved
2 tablespoons melted butter or olive oil
Juice of half a lemon
1 tablespoon minced fresh thyme
Heat the oven to 450º. Cut out the backbone of the chicken using a pair of sharp kitchen scissors, then cut through the cartilage to flatten the breast. Watch this video if you need a visual.
Generously season the cavity with salt and pepper, then transfer the chicken to a 12-inch cast iron skillet or a roasting pan, placing the chicken breast-side up. Pat the skin dry with a paper towel, then generously season the skin with more salt and pepper.
Toss together the melted butter, potatoes and more salt and pepper in a large bowl. Scatter the potatoes around the chicken. Roast the chicken for 30 to 45 minutes, stirring the potatoes halfway through. The chicken is done when the thighs reach 165ºF.
Remove the dish from the oven. Squeeze the lemon all over the chicken, then sprinkle with fresh thyme. Allow to rest for about 10 minutes (if you can wait that long; I certainly couldn’t) before carving and serving.