This is my best roast chicken. It's only slightly more work than simply throwing the bird in the oven, but I think it's more than worth it. I make it on Tuesdays to have leftovers all week, and I make it for dinner parties. It's always popular. And I personally believe that this gravy, swimming with softened onions and mushrooms, is perfect- especially with sliced chicken over egg noodles. Talk about comfort.
Oh, and an ingredient note: I rarely use dried herbs, but they really work best here.
Preheat oven to 400 degrees F. Bring chicken to room temperature. Mix together butter, dijon, honey, dried thyme and parsley, and onion powder. Use one hand to separate the skin of the chicken from the flesh, and use the other hand to slather this delicious compound between the skin and the flesh. Use as much of it as you can- don't forget the joints and the drumsticks. Wash your hands, and rub 2 T olive oil into the skin, and aggressively season the skin with salt and pepper. Set aside.
Line bottom of a roasting pan with sliced onion. Scatter mushrooms in there. Juice half a lemon over the vegetables, and throw the lemon half in there too. Place chicken on bed of vegetables, and pour wine in bottom of pan. Roast for 30 minutes breast down. When you go to flip the bird so that the breast is up, make sure there's enough liquid in the bottom of the pan. If it looks like the onions are burning (usually this happens in the corners), add some more wine, or chicken stock, or even water to keep it all moist. After roasting for an additional 30 minutes with the breast up, the skin should be golden and crisp, and the flesh should be cooked and juicy. Remove the chicken from the pan, put on a plate, and tent with foil.
While the chicken is resting, put the roasting pan on a burner. Remove the half of lemon. There should be plenty of liquid with browned and softened onions and mushrooms in the bottom of the pan. If there isn't plenty of liquid, add 1/2 cup water. Sprinkle with the flour, and over a low flame, whisk to make a thick gravy. Try to get any browned bits of chicken juice or caramelized onion from the bottom of the pan. Taste and season as necessary. Serve gravy with sliced chicken.