A roast chicken is one of the easiest, and most rewarding, dinners you can make. This version, with its mix of parsley, rosemary, thyme, basil, cilantro, sage, tarragon, chives, and/or oregano comes together quickly and is truly satisfying.
Position a rack in the lower third of the oven and preheat it to 450°F (230°C).
Finely grate the zest of the lemon into a small bowl, reserving the lemon. Toss in the butter, minced herbs, and finely chopped scallions and mash the ingredients together until well blended. Season with salt and pepper. Divide the seasoned butter in half. Wrap 1 piece tightly in plastic wrap and freeze for your next chicken or another use. Use the rest for the chicken.
Pour the oil into a Dutch oven swish it around so that it slicks the sides of the pot.
Pat the chicken completely dry with paper towels. Use your fingers to gently pull the chicken skin away from the meat, loosening it along the breasts and drumsticks. Work from the top and bottom of the chicken, lifting the skin up with your knuckles to help you open up some space without tearing the skin. Use a chunk of herb butter at a time and squish, squiggle, and otherwise schmush most of the butter under the skin of the chicken, spreading it as best you can against the meat. Don’t worry about getting it in an even layer—the butter will melt and baste all the meat in the oven. Any butter that plops off the chicken can be rubbed all over the skin. Season the chicken inside and out with salt and pepper and stuff the cavity with the reserved herb stems and scallion greens. Squeeze the half lemon over the bird and tuck the lemon inside the cavity.
Place the chicken, breast side up, in the Dutch oven. Toss in the onion and bay leaf and then pour the wine or water around the chicken and roast, uncovered, until done, 60 to 80 minutes, depending on the size of your chicken. If it looks as if the pan juices are running low, add some water. The chicken is done when a thermometer poked into the thickest part of a thigh registers 165°F (75°C). Alternatively, you can test for doneness by cutting a slit in the chicken between the drumstick and breast and check that the juices run clear.
Transfer the chicken to a cutting board and let rest for about 10 minutes. Meanwhile, skim the fat from the surface of the pan juices, discard the bay leaf, and, if desired, stir in some sherry vinegar.
Carve the chicken and serve with the pan juices on the side.