Line a baking sheet with tin foil then place a cooling rack on top. Combine the panko crumbs, fresh basil, lemon zest, oregano, garlic powder, sea salt, and freshly cracked pepper, to taste, together on a plate. Whisk the egg and milk together in a bowl. Dip the chicken breasts into the egg mixture and then coat them evenly in the panko mixture. Place each chicken breast on top of the cooling rack. Place the baking tray into the refrigerator for 30 minutes. Side Note: Don't skip this last step, it helps the panko stick to the chicken.
Preheat the oven to 400 degrees. Coat the chicken breasts with olive oil cooking spray. Place into the oven and bake for 30 minutes, or until chicken is cooked through. Turn the oven to broil, and cook for a few minutes, watching carefully, to brown the panko topping. Make sure you don't let it burn. Remove from the oven and let the chicken rest for 5 minutes.
While the chicken is resting. Add olive oil to a small skillet over medium heat. Add the tomatoes and let them cook for 2-3 minutes then add the kalamata olives and minced garlic. Season with sea salt and freshly cracked pepper, to taste. Cook, stirring constantly, for 1 minute. Remove from the heat.
Slice the chicken pieces then top with the tomato mixture. Sprinkle the top with feta cheese and fresh basil. Serve immediately. Enjoy.