Heat olive oil over a Dutch oven or sauté pan set over medium heat.
Cube chicken into bite-size pieces, and season with salt and pepper. Add chicken to the hot oil, cooking until very little pink is visible. The chicken will go back into the pan to cook, so no need to cook it all the way! Use a slotted and spoon to remove the chicken from the pan, transferring to a bowl and setting aside.
Add sun-dried tomatoes and about 1 tablespoon of the oil to the pan, followed by Italian seasoning, chopped onion and grated garlic. Stir and cook until fragrant.
Add orzo, chicken stock, and cooked chicken, stirring to combine. Cover and allow to cook for about 12 minutes, or until orzo is al dente (or cooked your liking).
Stir in the spinach, half-and-half, and parmesan cheese. Taste and season with additional salt and pepper to your liking. Serve with extra parm and enjoy!