Preheat the grill.
Salt and pepper the chicken well all over. Place it in a shallow glass container and let it marinate with the lemon juice, parsley, garlic and olive oil.
Meanwhile place in a small food processor the parsley, capers, garlic, lemon juice, olive oil. Chop fine. Place in a small container and add the salt and pepper to taste.
The salsa has to have tanginess from the lemon, and be smooth from the olive oil.
Barbeque the chicken and baste with the marinate as it is cooking.
Place the 2 small lemons sliced in half alongside the chicken. Remove the lemons when done to retain the juice.
Serve the chicken with salsa and juice from the roasted lemons.
Parsley, Lemon, Garlic Salsa