1 stick margarine, room temperature
1 tablespoon fresh parsley, checked and chopped
5-6 sprigs fresh parsley
1 teaspoon dried thyme
1 teaspoon dried rosemary
1/2 teaspoon kosher salt, plus more
1 4-5 pound whole chicken, rinsed, patted dry
Freshly ground pepper, to taste
3 medium onions, peeled, quartered lengthwise
15 garlic cloves, peeled
1/2 cup dry white wine
1 1/2 teaspoons flour
Preheat oven to 400 degrees F. Mix margarine, chopped herbs, and ½ teaspoon kosher salt in bowl; blend well to make herb butter.
Sprinkle cavity of chicken with salt and pepper; fill with herb sprigs. Starting at neck end, slide fingers under skin of breast and upper part of legs, loosening skin. Spread 3 tablespoons herb butter under skin on breast and upper leg meat. Place chicken on a rack in a large roasting pan and tie the legs together loosely to hold its shape. Scatter onions around chicken. Brush chicken and onions with 2 tablespoons herb butter; sprinkle with some more salt and pepper.
Roast the chicken, uncovered, for 30 minutes. Remove pan from the oven. Scatter garlic cloves around chicken. Brush chicken, onions and garlic with 1 tablespoon herb butter. Roast chicken and vegetables another 30 minutes. Reserve 1 tablespoon herb butter for sauce; brush remainder on chicken and vegetables. Continue to roast until chicken is golden about 30 minutes longer or a thermometer inserted into thickest part of thigh registers 180 degrees F.
Insert a wooden spoon into the cavity and tilt the chicken so that juices drain back into the pan. Transfer chicken to platter; surround with onions and garlic. Cover lightly with foil.
Place the roasting pan on the stovetop over medium-high heat. Add wine; bring to a simmer, scraping up browned bits on the bottom of the pan. Spoon off fat and discard it. Pour juices into a medium saucepan. Stir reserved 1 tablespoon herb butter and flour in small bowl to smooth paste. Bring pan juices to simmer; whisk in paste. Simmer gravy until slightly thickened, whisking occasionally, about 4 minutes. Season gravy with salt and pepper to taste. Serve chicken with gravy.