To spatchcock a bird is to remove its spine and flatten the poultry before roasting it. The purpose of this technique is twofold: It lessens the roasting time and it provides for more even cooking of the white and dark meat.
For garlic herb cheese: Preheat oven to 375 degrees F.
Finely chop herbs. Place soft cheese in small mixing bowl. Combine the soft cheese with herbs, finely grated or pasted garlic and lemon juice and zest (or unwrap store-bought Boursin cheese) and place in a small bowl.
For the spatchcock chicken: Work with raw poultry on a clean rubber board.
Have a large foil-lined rimmed baking sheet with a wire rack set inside of it near the cutting board you're working on.
Clip tips of wings with poultry shears. Place chicken breast-side down and remove the spine of the bird by cutting along either side of it in slow even strokes with shears, then turn the bird over and evenly press down on the breastbone to flatten the bird out.
Loosen the skin under the breasts and over the thigh and leg meat and evenly distribute the cheese. Drizzle the skin with EVOO or spray lightly with non-aerosol cooking spray, then season with kosher salt and coarse black pepper.
Roast chicken on middle rack for 15 minutes, then reduce heat to 350 degrees F and roast 40 to 45 minutes more to an internal temperature of 160 to 165 degrees F.
The garlic herb cheese is a delicious spread for vegetables, crackers and snacking. If you prefer a shortcut, substitute two 5-ounce packages Boursin cheese or one 8-ounce tub of prepared garlic herb cheese.