Sauté the Aromatics: In a large pot or Dutch oven, melt the butter over medium heat. Add the diced onion and cook for about 5 minutes until softened and translucent. Stir in the minced garlic and cook for another minute until fragrant.
Build the Broth: Pour in the chicken broth and bring to a gentle simmer. Stir in the dried thyme, garlic powder, salt, and pepper. Add the cooked chicken and let it warm through for 2-3 minutes.
Add the Gnocchi: Add the gnocchi directly to the simmering broth. Cook according to the package directions (usually 2-4 minutes for shelf-stable gnocchi, or until they float to the top if using frozen).
Make it Creamy: Reduce the heat to low. Slowly pour in the heavy cream while stirring gently to combine. Stir in the grated Parmesan cheese until it melts into the soup.
Wilt the Spinach: Add the chopped spinach and stir until it wilts into the soup (about 1-2 minutes). Taste and adjust seasoning with more salt and pepper if needed.
Serve and Enjoy: Ladle the hot soup into bowls and top with extra Parmesan cheese, freshly cracked black pepper, and a sprinkle of fresh herbs if desired. Serve immediately with crusty bread!