In a shallow bowl, mix flour and garlic powder. Pound thicker pieces of chicken to 1/4-inch thickness with the flat side of a meat mallet, if needed. Cut each piece in half (to make smaller serving sizes) and sprinkle with 1/2 teaspoon salt and pepper. Dip both sides of chicken in flour mixture to coat lightly and shake off excess.
Heat 2 tablespoons oil in a large skillet over MEDIUM heat. Add half of the chicken and cook 4 to 5 minutes on each side or until golden brown and chicken is fully cooked through. Transfer cooked chicken to a plate and tent with a piece of foil to keep warm. Repeat with remaining oil and chicken. When finished, lightly wipe excess oil from skillet.
Return skillet to the heat and add broth and orzo. Bring to a boil, reduce heat and simmer, covered, 8-10 minutes or until tender. Remove cover and stir in spinach, tomatoes, the juice of one lemon, basil and remaining 1/2 teaspoon salt. Remove the skillet from the heat. Return the cooked chicken to the skillet and sprinkle with about half of the Parmesan.
Cut remaining lemon into wedges. Serve with remaining Parmesan and lemon wedges on the side.
Notes
I like to use the finest grate on my box grater when grating the Parmesan for an almost powdery consistency like you see in the images in this post.