Cook pasta according to package instructions. Drain and rinse briefly with cool water, then set aside to cool.

In a bowl, toss chicken with olive oil, lemon juice, garlic, oregano, salt, and pepper. Heat a large skillet over medium high heat and cook for 5–7 minutes per side, or until fully cooked through, adjusting heat as necessary to prevent the outside burning. Let the chicken rest 5 minutes on a cutting board, then cut into bite size pieces or strips.

Whisk together all dressing ingredients until smooth and well combined.

In a large bowl, combine cooked pasta, chicken, cucumber, tomatoes, red onion, olives, avocado, and herbs.

Pour the dressing over the salad and toss gently to combine. Add feta, if using, and toss lightly again.

Serve immediately or chill for 30–60 minutes for the best flavor. Store leftovers covered in the refrigerator for up to 3 days.