Put garlic, basil, cilantro, parsley, rosemary, oil, salt and pepper in a blender. Starting on medium speed, blend everything together. Increase to high speed make sure everything is blended well. Once everything is homogenous, pour out into a large bowl.
Very carefully cut along both sides of the backbone of the whole chicken to remove it, splitting the chicken, then cut down the breastbone to cut the chicken in half. Place the chicken halves in marinade. Let the chicken hang out in the marinade at room temperature for at least 1 hour or up to overnight in the fridge.
Preheat a grill for cooking at medium-high heat. Lightly oil the grill grates. Place the chicken skin-side down on grill and place a brick on top of each piece to weigh them down. Let cook 5 minutes, then flip chicken and continue to press with bricks. Let cook until the chicken is fully cooked and its internal temperature reaches 165 degrees F, about 10 minutes. Let chicken rest for 5 minutes.
Meanwhile, begin warming Chickpea Conserva in its liquid. When the chickpeas are hot, plate them on a large serving platter and arrange the chicken on top. Serve immediately.
Soak chickpeas in water at room temperature for at least 12 hours.
Drain chickpeas well. Add olive oil, pancetta, carrots, celery, fennel, onions, garlic and thyme to a large saute pan over medium-high heat, and cook, stirring occasionally, until golden brown. Add chickpeas and saffron and cook for 1 minute. Add chicken stock and cook for 15 minutes. Season with salt and cook until the chickpeas reach desired consistency, another 45 minutes. Take off heat, finish with lemon juice and pour chickpeas with their liquid into a pan set in ice to cool. Store the chickpeas in their liquid.
This recipe has been updated and may differ from what was originally published or broadcast.