Yield: 6 servings.
For the chicken:
6 boneless, skinless chicken breasts
½ cup extra-virgin olive oil
4 large garlic cloves, minced
1 teaspoon dried oregano
1 teaspoon salt
½ teaspoon freshly ground black pepper
2 teaspoons lemon zest, from 2 lemons
For the relish:
1 cup sweet onion, chopped
2 garlic cloves, chopped
1 cup pitted Kalamata olives, chopped
1 cup sun-dried tomatoes (preferably packed in oil), roughly chopped
1 tablespoon capers
½ cup fresh parsley, chopped, plus more for garnish
½ cup extra-virgin olive oil, divided
¼ teaspoon freshly ground black pepper
For the chicken: Place chicken breasts between 2 pieces of wax paper and, using a meat mallet, pound chicken to an even ½-inch thickness.
In a 1-gallon ziplock bag, mix olive oil, garlic, oregano, salt, pepper, and lemon zest. Add chicken breasts and massage marinade into meat until evenly coated. Seal the bag and place in a bowl in the refrigerator. Let the chicken marinate at least 4 hours or overnight.
Preheat grill to high. Lightly dip a clean kitchen towel in vegetable oil and, using tongs, carefully rub over clean grill grates several times until well coated. Place marinated chicken breasts on the grill.
Close lid on grill and cook chicken for 2 to 3 minutes per side. Remove chicken from grill and place on a platter. Cover with foil and allow chicken to rest 5 minutes before serving.
For the relish: Add ¼ cup olive oil to sauté pan and heat on medium, just until pan is hot. Add chopped onions and cook for 5 to 10 minutes or until onions are soft. Add garlic and stir for 1 to 2 minutes. Remove from heat.
Place onion and garlic mixture in a mixing bowl and add remaining ingredients. Toss until all ingredients are combined. Serve over grilled chicken breast with a loaf of crusty bread on the side.