To a large Crockpot, stir together broth, carrots, celery, garlic powder, onion powder, flaky poultry seasoning, basil, salt, pepper and chicken.
Cover and cook on low for 5-6 hours or on high for 3-4 hours.
Uncover and either break apart the chicken inside the Crockpot with a meat chopper or transfer to a bowl, shred with 2 forks, and return to the Crockpot.
In a small bowl, whisk together cornstarch and milk.
To the Crockpot, stir in the cornstarch slurry, gnocchi, and spinach.
Set the Crockpot to the high setting, if not already set on high. Cover and cook until the potato gnocchi is cooked through (15-20 minutes).NOTE: Check pre-package gnocchi directions for the recommended cook time. Some brands require only 5 minutes, so make sure you don't over cook them or they'll dissolve. Stir in parmesan cheese. Taste and adjust seasonings to preference. Garnish with parmesan cheese and crushed red pepper flakes.