Bring a large pot of salted water to a boil. Add orzo and cook al dente, about 8-10 minutes. Drain and set aside.
Season chicken with salt, pepper, half the oregano, and half the basil.
Heat olive oil in large skillet over medium-high. Sear chicken 6-7 minutes per side until cooked. Remove and slice.
Sauté onion 3-4 minutes. Add garlic, cook 1 minute.
Add tomatoes, spinach, olives, remaining herbs. Wilt spinach 2-3 minutes.
Pour in broth, simmer 5 minutes.
Add orzo and chicken. Toss to coat.
Stir in feta and lemon juice. Season to taste.
Garnish with parsley and serve.