Directions

1. 1

   Set up your grill for medium-high heat, creating both direct heat (over coals or flames) and indirect heat (away from heat source) zones. Use hardwood or hardwood charcoal if possible. Strip leaves from 5 rosemary sprigs and coarsely chop them; set aside. Bundle the remaining rosemary sprigs together and secure tightly with kitchen twine to create a basting brush. Pour the olive oil into a small bowl or cup and stir in the smashed garlic cloves; let sit while you prepare the chicken.

2. 2

   Place the whole chicken breast side down on a large cutting board. Using kitchen shears, cut along both sides of the backbone to remove it entirely (save for stock if desired). Flip the chicken over so it's breast side up, then press down firmly on the breastbone with the heel of your hand until you hear it crack and the chicken lies as flat as possible. Tuck the wing tips behind the breasts and tuck the legs in so the drumsticks point outward, creating the flattest possible profile.

3. 3

   Place both the spatchcocked whole chicken and the chicken breast on a work surface. Using your rosemary brush, coat all surfaces of both pieces generously with the garlic-infused oil. Sprinkle the chopped rosemary leaves, kosher salt, and black pepper evenly over all sides of both pieces of chicken, pressing gently so seasonings adhere.

4. 4

   Place both pieces of chicken skin side down directly over the hot part of the grill. Let them cook undisturbed for about 5 minutes, until the skin is golden brown, crispy, and lightly charred. Flip both pieces skin side up, then move them to the indirect heat zone (away from direct flames or coals). Brush both pieces again with the garlic-oil using the rosemary brush.

5. 5

   Continue grilling in the indirect heat zone, basting the chicken with the rosemary brush and garlic-oil every 10–15 minutes, until an instant-read thermometer inserted into the thickest part of the thigh or breast registers 165°F. The whole chicken will take approximately 45–60 minutes total, while the chicken breast will be done in 25–35 minutes. When fully cooked, the skin should be golden brown and crispy, and the juices should run clear when pierced.

6. 6

   Transfer the cooked chicken to a cutting board and let rest for at least 10 minutes before carving. This allows the juices to redistribute throughout the meat. Arrange the carved chicken on a serving platter and serve warm with chimichurri sauce on the side for drizzling or dipping.