Cook pasta according to package instructions. Drain and set aside.
Season chicken with salt, pepper, and Italian seasoning.
Heat olive oil in a skillet over medium heat. Cook chicken for 6–8 minutes per side until fully cooked (165°F internal temperature). Let rest, then slice.
In the same pan, sauté garlic and dried tomatoes for 1–2 minutes.
In a bowl, whisk flour, milk, and Parmesan cheese until smooth.
Add the mixture to the pan along with spinach. Simmer until the sauce thickens and spinach wilts.
Stir in cooked pasta and sliced chicken until coated.
Garnish with parsley and black pepper. Serve immediately.