1-First, preheat your oven to 425°F (220°C) and get all ingredients ready. Rinse the whole chicken under cold water, pat it dry with paper towels, and remove any giblets or excess fat to start fresh.

2-Next, season the inside of the chicken generously with kosher salt and freshly ground black pepper. Stuff the cavity with the large bunch of fresh thyme, halved lemon, and head of garlic cut in half crosswise for added flavor.

3-Then, brush the outside with 2 tablespoons of melted butter and season again with salt and pepper. This step ensures the skin gets crispy and the meat stays moist.

4-After that, tie the legs together with kitchen string and tuck the wing tips under the body. Scatter the thickly sliced Spanish onion around the chicken in the roasting pan for extra taste.

5-Roast the chicken for about 1.5 hours, or until the juices run clear when you check between the leg and thigh. Once done, remove it from the oven and cover with foil to rest while you make the gravy.

6-Finally, for the gravy, skim off the fat from the pan but save 2 tablespoons of it. Add 1 cup of chicken stock, cook on high heat for about 5 minutes to reduce, then mix in the reserved fat with 2 tablespoons of all-purpose flour. Bring it to a boil, strain into a saucepan, season as needed, and keep warm.