1. Heat the olive oil in a large skillet or Dutch oven over medium-high heat. Add the cubed chicken breast to the hot skillet. Season with Italian seasoning, garlic powder, salt, and pepper. Cook, stirring occasionally, until the chicken is browned on all sides and cooked through, about 5-7 minutes. The chicken should no longer be pink in the center. Remove the cooked chicken from the skillet and set it aside on a plate.

2. In the same skillet, add the chopped onion. Cook over medium heat, stirring occasionally, until the onion softens and becomes translucent, about 3-4 minutes. Add the minced garlic and cook for another minute until fragrant, being careful not to burn it. The kitchen will start to smell wonderful at this point.

3. Pour in the undrained diced tomatoes and chicken broth. Bring the mixture to a gentle simmer, scraping up any browned bits from the bottom of the skillet with a wooden spoon. This helps to incorporate all the delicious flavors.

4. Stir in the heavy cream and the potato gnocchi. Make sure the gnocchi are submerged in the sauce as much as possible. Bring the mixture back to a simmer, then reduce the heat to medium-low. Cook, stirring occasionally, for 5-7 minutes, or until the gnocchi are tender and have puffed up slightly. They should be soft to the touch when gently pressed.

5. Return the cooked chicken to the skillet. Stir in the grated Parmesan cheese until it melts and the sauce thickens slightly. The cheese will help bind the sauce and add a lovely savory depth.

6. Finally, add the fresh spinach to the skillet. Cook, stirring gently, until the spinach wilts down into the sauce, which usually takes just 1-2 minutes. The vibrant green of the spinach will add a beautiful pop of color and freshness.

7. Taste and adjust seasoning if necessary. Serve hot, garnished with extra grated Parmesan cheese if desired.