Chop butter into cubes. Rub the chicken with one tablespoon and stuff the rest inside the cavity. Cut the lemon in half and squeeze the entire lemon over the chicken. Add the lemon to the cavity. Chop about a tablespoon of fresh herbs. Rub the chopped herbs over your chicken. Add a few sprigs of fresh herbs in the cavity. Stuff that baby full of fresh goodness. Add the onion and whole garlic cloves peeled to the cavity.
Sprinkle the outside with salt and fresh pepper.
Cover with foil or if your roaster has a top, cover and bake for 30 minutes at 425º.
After 30 minutes turn the temp down to 375º and continue to bake for about 40 more minutes.
When the chicken is ready, the leg should wiggle and pull away without much effort, and the juices should run clear.