Preheat the oven to 425°F (220°C). Pat the whole chicken dry inside and out with paper towels. In a small bowl, mix 3 tbs olive oil, minced garlic, lemon zest from 1 lemon, lemon juice from half the lemon, chopped thyme, chopped rosemary, 1.5 tsp salt and 1 tsp pepper. Rub the softened butter under the skin on the breast (sliding fingers gently between skin and meat) and spread half of the lemon-herb oil mixture over the buttered breast and the other half all over the exterior of the bird. Season the cavity lightly with salt and pepper and optionally place the squeezed lemon halves and 2 sprigs of thyme inside the cavity for extra aroma.

Truss the chicken loosely with kitchen twine (tie legs together and tuck wing tips under) so it cooks evenly. Let the chicken rest at room temperature for 15 minutes while you prepare the vegetables (this brings the bird closer to oven temperature and improves roasting).

Roast Vegetables

Prep vegetables and arrange in pan

Toss the baby potatoes, carrots, halved shallots and asparagus pieces with 2 tbs olive oil, 3/4 tsp salt and 1/2 tsp pepper in a bowl until evenly coated. Spread vegetables in a single layer in a large roasting pan or rimmed baking sheet, leaving a central space for the chicken so heat circulates. Place the trussed chicken breast-side up on top of some potatoes (this elevates the bird slightly and lets juices flavor the veg).

Roast

Roast in the preheated 425°F (220°C) oven for 50–60 minutes, basting once at 25–30 minutes with pan juices and the remaining lemon-herb oil if desired. After about 35–40 minutes check vegetables: if they are browning too quickly, give them a turn and move smaller pieces away from direct heat. The chicken is done when an instant-read thermometer inserted into the thickest part of the thigh (not touching bone) reads 165°F (74°C) and the juices run clear.

If asparagus was included and you prefer it more tender-crisp, add asparagus during the last 12–15 minutes of roasting rather than at the start so it does not overcook. For even browning, rotate the pan halfway through roasting.

Pan Sauce & Finishing

Rest the chicken and make pan sauce

When the chicken reaches temperature, transfer it to a cutting board and tent loosely with foil. Let rest 10–15 minutes to let juices redistribute. While the chicken rests, place the roasting pan over medium heat on the stovetop (or use a skillet) and carefully pour off excess fat, leaving about 1–2 tbs and any browned bits. Add 1/2 cup white wine (or 1/2 cup chicken stock) to deglaze the pan, scraping up browned bits with a wooden spoon. Let it reduce by half (about 2–3 minutes). Add 1/2 cup chicken stock and 1 tbs fresh lemon juice and simmer 2–3 minutes more until slightly reduced.

Remove from heat and whisk in the cold cubed butter 1 piece at a time to emulsify and slightly thicken the sauce. Stir in chopped parsley and adjust seasoning with salt and pepper to taste.

Carve and serve

Carve the rested chicken into pieces and arrange on a platter with the roasted vegetables. Spoon the pan sauce over the chicken and vegetables, garnish with lemon wedges and additional parsley. Serve immediately.