In a large saucepan, pour in the Alfredo sauce and water to create the soup base. Stir well to combine, then add the chopped rotisserie chicken, Italian seasoning, salt, and pepper. Place the saucepan over medium heat and bring the mixture to a gentle boil, stirring occasionally until it starts to bubble and thicken, about 5 minutes.

Once the soup base is bubbling, carefully add the potato gnocchi and fresh spinach to the pot. Stir gently to ensure the gnocchi are submerged. Cook for 3 to 8 minutes, watching closely for the gnocchi to float to the top, which indicates they are cooked through. The spinach should also wilt beautifully.

After the gnocchi have floated and the spinach is tender, remove the soup from heat. Ladle the creamy Chicken Gnocchi Pesto Soup into bowls. Top each serving with 1 teaspoon of prepared pesto, swirling it in for an extra burst of flavor. Serve warm.