Start by heating a skillet over medium heat and add the oil from the sundried tomatoes. Once hot, toss in the cubed chicken. The oil will help keep the chicken moist and prevent sticking.
Next, season the chicken generously with 1 teaspoon of Italian seasoning, salt, paprika, red pepper flakes, and black pepper. Give everything a good mix, ensuring each piece of chicken is evenly coated.
Cook the chicken until it turns a lovely golden brown. You’re looking for a nice sear on all sides, which should take about 6 to 8 minutes. Once browned, sprinkle the chicken with grated Parmesan and remove it from the skillet. Set it aside for later.
In the same skillet, add butter, followed by the onion and minced garlic. Sauté this mixture until the onion is translucent and the garlic is fragrant, usually about 5 minutes.
After the onions are tender, sprinkle in the remaining 1 teaspoon of Italian seasoning. Stir to combine, allowing the seasoning to infuse the butter and the onions.
Now, pour in the water and add the heavy whipping cream. Stir well to combine, and bring the mixture to a gentle boil.
Once boiling, add the uncooked pasta to the skillet. Stir it in so that it’s fully submerged in the sauce and cook according to the package directions, usually around 8 to 12 minutes. Keep an eye on it to ensure it doesn't overcook.
When the pasta reaches your desired tenderness, reduce the heat and stir in the fresh spinach, along with the cooked chicken and the reserved sundried tomatoes. Mix everything until heated through, about 2 to 3 minutes.
Finally, top your creation with shredded Parmesan cheese and let it melt slightly before serving. This will add an extra layer of flavor!