Season the chicken breasts with a few drizzles of olive oil, 1 teaspoon garlic powder, 1 teaspoon Italian seasoning, Kosher salt (about ½ teaspoon per breast), and ground black pepper.
In a large skillet, heat a few generous drizzles of olive oil over medium heat. Cook the chicken, about 6 minutes per side, or until fully cooked through in the center. Remove from the skillet and let it rest for 10 minutes. Then, slice.
In the same skillet, melt the unsalted butter. Then, sauté onions until softened. Next, add the minced garlic and the remaining 1 teaspoon of Italian seasoning, and sauté for another 1 minute until fragrant.
Stir in the orzo pasta for about 2 minutes, followed by the chicken broth. Season with salt and pepper to taste. Bring to a low boil, then reduce to a simmer. Cover and cook for 12 minutes.
Once the orzo is tender, uncover and stir in the spinach, heavy cream, and parmesan cheese.
Finish with lemon zest and freshly squeezed lemon juice (to taste).
Serve with the sliced chicken on top, and garnish with lemon slices and Italian parsley.