Heat olive oil in a large skillet over medium heat. Add chopped onion and cook until translucent, about 3-4 minutes. Stir in minced garlic and cook for another 30 seconds until fragrant. Add diced chicken, season with salt, Italian seasoning, and red pepper flakes. Cook until chicken is browned and cooked through, about 6-8 minutes. Remove chicken and set aside.

In the same pan, pour in chicken broth and bring to a simmer. Stir in orzo and cook, stirring occasionally, until orzo is tender and has absorbed most liquid, approximately 8-10 minutes. Reduce heat to low.

Stir in heavy cream and grated Parmesan cheese. Mix well until the sauce is creamy and smooth. Add the cooked chicken back to the skillet along with fresh spinach. Cook for 2-3 minutes, until spinach wilts and everything is heated through. Season to taste with more salt or spices if needed. Serve hot and enjoy the punchy, savory, satisfying flavors.