Heat oven to 350F and arrange rack in center of oven. Layer lemon slices on the bottom of a large baking dish with a lid. Set aside.

Press 2 garlic cloves through a garlic press. Lift the skin from 1 breast and rub garlic between skin and breast. Repeat with remaining chicken breasts and garlic cloves.

Drizzle oil and lemon juice over chicken breasts. Sprinkle with salt and pepper and rub into skin. Place chicken breasts over the lemon slices in prepared pan.

Combine mint and oregano in a small bowl. Sprinkle over chicken breasts. Add olives to pan.

Transfer to oven and bake 40 minutes, until juices run clear.

Remove from oven, sprinkle with feta, bake 5 minutes more and serve.