For an irresistible one-pan Sunday dinner, roasted lemon-tarragon chicken—left untrussed for the crispiest skin—rests atop a bed of onions with carrots, potatoes, celery, and garlic.
Preheat oven to 400 degrees. Rub chicken inside and out with one garlic half. Place both garlic halves and the tarragon sprigs in cavity. Stir together butter, shallot, chopped tarragon. Season with salt and freshly ground pepper. Loosen skin of chicken near cavity with hands; spread butter mixture under skin all over flesh.
Squeeze juice from lemon halves over chicken; place in cavity. Season with salt and freshly ground pepper.
Halve the large onions horizontally at an angle. Arrange in the middle of a 9-by-13-inch roasting pan to form a square. Position halves so that the slanted ends of each pair face each other, inward, and almost touch. Place chicken, breast side up, on onion "rack."
Quarter the small onions; arrange with carrots, celery, and potatoes around bird. Tuck lemon slices between wings and breast, and legs and breast. Pour wine and stock over vegetables.
Roast chicken and vegetables, basting 2 or 3 times with pan juices, until an instant-read thermometer inserted into thickest part of chicken thigh registers 165 degrees and juices run clear, 1 to 1 1/2 hours.
Remove pan from oven, and let chicken stand 10 minutes. Carve chicken. Arrange chicken and roasted vegetables (including rack onions) on a platter. Spoon pan juices over meat.
Red onions -- cut at an angle -- form a V-shaped roasting rack for the chicken.
On "Mad Hungry," Lucinda omitted the celery, carrots, potatoes, wine, and stock used in step 4.