Combine the lemon zest, lemon juice, olive oil, 2 tablespoons rosemary and a dash of salt and pepper in a small bowl.
Put the chicken in an oven-proof skillet. (a 10-inch cast iron skillet works well). Pour the lemon/herb mixture over the chicken.
Add the garlic cloves to the pan and distribute as evenly as possible.
Roast for about 40 minutes, until the chicken is done.
Remove the chicken from the pan to a plate. Add the chicken broth to the skillet and cook on the stovetop over medium heat for a couple of minutes, scraping up the tasty cooked bits from the bottom of the pan.
Add the green olives and cook just a minute more.
Pour the sauce over the chicken and garnish with the extra tablespoon of chopped rosemary.