Take the chicken out of the refrigerator 30–45 minutes before roasting so it comes closer to room temperature — this helps it cook more evenly. Preheat your oven to 425°F.

Pat the chicken completely dry inside and out with paper towels. This is the single most important step for crispy skin — any moisture will steam the skin instead of crisping it.

In a small mixing bowl, mix together the 4 tbsp mantequilla sin sal ablandada a temperatura ambiente softened to room temperature, 4 dientes de ajo 2 picados minced, 1 tbsp romero fresco finamente picado finely chopped, thyme leaves, 1½ tsp 1 ½ tsp sal kosher para el untado con mantequilla, and ½ tsp ½ tsp pimienta negra until well combined.

Using your fingers, gently loosen the skin over the breast and thighs by sliding your hand underneath. Push about half of the herb 4 tbsp mantequilla sin sal ablandada a temperatura ambiente under the skin and massage it evenly over the meat. Rub the remaining mantequilla sin sal ablandada a temperatura ambiente all over the outside of the chicken. Drizzle 1 tbsp 1 tbsp aceite de oliva over the top and rub it in.

Season the cavity generously with 1 ½ tsp sal kosher para el untado con mantequilla and ½ tsp pimienta negra. Stuff the cavity with the 1 limón entero halves (give them a squeeze first), 4 dientes de ajo 2 picados cloves smashed, 1 cebolla amarilla entera quartered, and fresh thyme sprigs if using. These aromatics perfume the chicken from the inside out.

Tie the legs together with kitchen twine (trussing) and tuck the wing tips under the body. This helps the chicken cook evenly and keeps the breast from drying out.

Toss the 3 zanahorias medianas and 3 tallos de apio with 1 tbsp 1 tbsp aceite de oliva and ½ tsp 1 ½ tsp sal kosher para el untado con mantequilla. Scatter them in the bottom of a roasting pan or large skillet oven-safe to form a rack for the chicken. Pour the chicken broth into the bottom of the pan — this keeps the drippings from burning and forms the base of a natural pan sauce.

Place the chicken breast-side up on top of the vegetables. Roast at 425°F for 20 minutes to get the skin browning and crisping.

Reduce the oven temperature to 375°F. Continue roasting for 50–60 more minutes, basting the chicken with the pan juices once or twice during cooking. A 4 lb chicken typically takes about 75–80 minutes total.

The chicken is done when an instant-read meat thermometer inserted into the thickest part of the thigh (without touching bone) reads 165°F. The juices should run clear when you pierce the thigh.

Transfer the chicken to a cutting board and tent loosely with aluminum foil. Let it rest for at least 15 minutes before carving. Resting is essential — it allows the juices to redistribute so every bite stays moist.

While the chicken rests, pour the pan drippings through a fine mesh sieve into a small saucepan. Skim off excess fat, bring to a simmer over medium heat, and reduce for 3–5 minutes for a simple, flavorful pan jus to drizzle over the carved chicken.