In a Dutch oven, brown chicken in 2 tablespoons butter. Remove and keep warm. In the same pan, saute the onion, carrot, celery and garlic in remaining butter until tender., Whisk in flour until blended; gradually stir in the milk, cream, bouillon and pepper. Bring to a boil. Reduce heat; cook and stir for 2 minutes or until thickened., Add the gnocchi and spinach; cook for 3-4 minutes or until spinach is wilted. Add the chicken. Cover and simmer for 10 minutes or until heated through (do not boil).