Grilled Lemon-Harissa Chicken

I found this recipe in a story from a California newspaper about a "Pacific Northwest cuisine" restaurant opening in Manhattan. I don't know what it has to to with any of the above places--it seems Middle Eastern or North African to me--but it sure is good!

• Ready In: 4 hrs
• Serves: 6

Ingredients

• 2⁄3 cup extra virgin olive oil
• 1⁄4 cup capers, drained and smashed
• 6  garlic cloves, minced
• 1⁄3 cup fresh lemon juice (1 to 2 lemons)
• 3  tablespoons  minced fresh rosemary
• 2  tablespoons paprika
• 1  tablespoon harissa (a spicy Moroccan seasoning blend)
• 1  teaspoon kosher salt
• 2  teaspoons fresh ground black pepper
• 6  boneless skinless chicken breast halves (about 3-1/2 pounds)
• 2 1⁄2 tablespoons all-purpose flour

Directions

1. To make the marinade, combine the olive oil, capers, garlic, lemon juice, rosemary, paprika, harissa, salt and pepper in a small bowl.
2. Pound the chicken breasts to an even 1/2-inch thickness.
3. Place the chicken in a large Ziplock bag and add the marinade. Make sure the chicken is coated on all sides, then refrigerate for at least 3 hours and up to 6 hours.
4. Prepare your grill by scraping it, oiling it and heating it to high.
5. Remove the chicken from the marinade, reserving the liquid. Place the chicken breasts a few inches apart on the grill. If you are using a charcoal grill, place the chicken directly over the hot coals.
6. Grill the chicken for 4 to 6 minutes on each side, or until cooked through (the chicken should read 165°F on a meat thermometer inserted in the center). Remove the chicken from the heat, cover with foil and set aside.
7. To make the sauce, in a medium saucepan combine the remaining marinade with 1 cup water. Bring to a boil and cook for 1-2 minutes.
8. Whisk the flour into 1/3 cup cool water, then add to the marinade, stirring constantly. Bring to boil to thicken the sauce slightly. Remove from the heat and cool slightly.
9. Pour the sauce over the chicken and serve.