In a large pot melt your butter over medium high heat.
Add in the carrots, celery, onion and garlic and cook for about 5 minutes until the onion starts to get translucent and the vegetables all start to get tender.
Add in the flour and stir together to create a roux (a thickener), cook for about 1-2 minutes.
Slowly pour in the chicken broth, while stirring. Add in the milk, and heavy cream the same way.
Allow to come to a boil, and lower temperature to medium or medium low and cook until thickened, for about 8-10 minutes.
Add in the Italian seasonings, salt, pepper, gnocchi, and chicken and cook for about 4 to 5 minutes, or until the gnocchi is cooked through (according to package directions).
Add in the chopped spinach and cook for another 2 minutes, until wilted.