Bring a large pot of salted water to a boil. Add pasta; cook for about 8–10 minutes or until al dente. Drain and reserve 1/4 cup pasta water.

In a large skillet, heat olive oil over medium heat. Add chicken, seasoning with salt, black pepper, paprika, and Italian seasoning. Sauté for 6–8 minutes until browned and cooked through. Remove from skillet.

In the same skillet, add more olive oil if necessary, then add minced garlic. Sauté for about 30 seconds. Add whole wheat flour and stir to create a roux. Gradually whisk in chicken broth and milk, stirring until sauce thickens (2–3 minutes).

Reduce heat to low and mix in Greek yogurt and Parmesan cheese until smooth. Use reserved pasta water if the sauce feels too thick.

Return cooked chicken and pasta to the skillet. If using, add baby spinach. Toss until pasta is well coated and spinach is wilted (about 1 minute).

Serve hot, garnished with chopped parsley.