Herbed Roast Chicken

This is from Cook's Illustrated. It's a long one, with a little extra work, but well worth it. The recipe says it serves 3-4, but it feeds my family of six. Just depends on what type of "eaters" you have.

Chicken
1 whole chicken (about 5 pounds), trimmed of excess fat, giblets discarded (see note)
1/2 cup table salt plus 1/4 teaspoon
1/4 cup fresh tarragon leaves , lightly packed
1 tablespoon fresh thyme leaves (see note)
6 medium scallions , green parts sliced thin (about 2/3 cup), whites reserved for another use
1 medium garlic clove , minced or pressed through a garlic press (about 1 teaspoon)
Ground black pepper
6 tablespoons unsalted butter , softened
1 tablespoon vegetable oil

Sauce
1 - 1 1/2 cups low-sodium chicken broth
2 teaspoons unbleached all-purpose flour
1 teaspoon fresh lemon juice from 1 lemon (I only use about 1/2 teaspoon)

Instructions

1. FOR THE CHICKEN: Following illustrations below, butterfly chicken and flatten breastbone. (to butterfly a chicken, use a pair of sharp kitchen shears and cut the backbone out so that the chicken will lay flat; then using the heel of your hand push down on the breast bone to help it lay flat) Tuck wings behind back. Using sharp knife, lightly score skin of thighs and legs, making 2 shallow cuts on each part about 1/8 inch into meat and about 3/4 inch apart. Dissolve 1/2 cup salt in 2 quarts cold water in large container to make the brine. Submerge chicken in brine, cover with plastic wrap, and refrigerate 1 hour.

2. Meanwhile, adjust oven rack to middle position and heat oven to 450 degrees. Place tarragon, thyme, scallions, garlic, remaining 1/4 teaspoon salt, and 1/4 teaspoon pepper on cutting board; mince to fine paste. Transfer herb paste to medium bowl and add butter. Using fork or stiff rubber spatula, mix until combined. Transfer 2 tablespoons herb butter to small bowl and refrigerate; set aside remainder at room temperature.

3. Remove chicken from brine and rinse under cold running water; pat dry with paper towels. Following illustrations below and using fingers, carefully separate skin from each side of breast to form pocket. Place 1 tablespoon softened herb butter in each pocket. Using spoon or fingers, spread butter over breast meat. Season skin with pepper.

4. Heat oil in oven safe 12-inch skillet over medium-high heat until just smoking. Place chicken skin-side down in skillet and reduce heat to medium. Cook until lightly browned, 8 to 10 minutes. Transfer skillet to oven and roast chicken 25 minutes. Using tongs, flip chicken so skin-side is facing up. Using spoon or spatula, evenly coat chicken skin with remaining softened herb butter and return to oven. Roast chicken until skin is golden brown and instant-read thermometer inserted in thickest part of breast registers 160 degrees and 175 degrees in thickest part of thigh, 15 to 20 minutes. Transfer chicken to carving board and let rest, uncovered, 20 minutes.

5. FOR THE SAUCE: While chicken rests, pour pan juices into fat separator; allow liquid to settle 5 minutes. Pour juices into 2-cup measuring cup and add enough chicken broth to measure 1 1/2 cups. Add 2 teaspoons fat from fat separator to skillet and place over medium heat. When fat is shimmering, add flour and cook, stirring constantly, until golden, about 60 seconds. Add broth and bring to simmer, scraping pan bottom to loosen browned bits. Simmer rapidly until reduced to 1 cup, 5 to 7 minutes. Stir in any accumulated chicken juices from carving board; return to simmer and cook 30 seconds. Remove pan from heat, whisk in cold herb butter and lemon juice; season with salt and pepper. Carve chicken and serve, passing sauce separately.