Bring a large pot of salted water to a boil. Cook the whole wheat pasta according to package directions until al dente. Reserve 1/2 cup pasta water, then drain the pasta and set aside.

Pat the chicken cubes dry with paper towels. Season them with salt, black pepper, paprika, and Italian seasoning.

Heat 1 tablespoon olive oil in a large skillet over medium-high heat. Add the chicken in a single layer. Cook without moving too much until golden, then stir occasionally until cooked through, about 6 to 8 minutes. Transfer the chicken to a plate.

Reduce heat to medium. Add the remaining tablespoon of olive oil and the minced garlic. Sauté 30 seconds to 1 minute until fragrant but not browned.

Sprinkle the whole wheat flour over the garlic and stir for 30 seconds to form a light roux. Slowly whisk in the chicken broth until the mixture is smooth.

Pour in the low-fat milk and bring to a gentle simmer. Cook 2 to 3 minutes until it begins to thicken slightly.

Remove the skillet from heat and stir in the plain non-fat Greek yogurt until the sauce is smooth. Stir in the grated Parmesan until melted. If the sauce is too thick, whisk in a splash of the reserved pasta water to loosen it.

Return the cooked chicken to the skillet. Add the drained pasta and baby spinach. Toss until the spinach wilts and everything is evenly coated. Taste and season with salt and black pepper.

Serve immediately, garnished with chopped fresh parsley and extra Parmesan if desired.