Cook the orzo in salted water, per instructions. Side Note: Sprinkle a little bit of chicken bouillon granules into the boiling water for extra flavor. Drain the orzo and all but 1/2 cup of cooking liquid through a colander.
While the pasta cooks, heat the olive oil in a large skillet over medium heat. Add the onion and season with a bit of crushed red pepper, oregano, sea salt, and freshly cracked pepper, to taste; cook stirring often, for 3-4 minutes. Remove the onion from the skillet and set aside. Season the chicken with a sprinkling of oregano, garlic powder, sea salt, and freshly cracked pepper, to taste. Place the chicken into the same skillet over medium-high heat (add cooking spray if needed). Sauté 6 minutes, turning to brown all sides. Remove chicken from pan; keep warm.
Turn the heat to low then add reserved cooking liquid to the skillet, making sure to scrape up all the browned bits off of the bottom of the pan; add the minced garlic and stir. Add the chopped tomato, softened onions, kalamata olives, and tomato paste, to the skillet; cook over medium-high heat for 2 minutes. Add chicken, orzo, basil, and spinach leaves, stirring until spinach wilts. Taste and re-season if needed. Remove from heat; sprinkle with cheese and serve. Enjoy.