In a large bowl, combine ground chicken, bread crumbs, eggs, sun-dried tomatoes, Parmesan, garlic, dried basil, salt, onion powder, pepper, and crushed red pepper flakes. Mix until just combined.
Form the mixture into 1-1/2-inch meatballs. This should yield approximately 20 meatballs.
Heat olive oil in a skillet over medium heat. Brown the meatballs on all sides, 1-2 minutes each. They don’t need to cook through, as they’ll finish cooking in the slow cooker.
Transfer the meatballs to your slow cooker. Add 2 cups chicken broth and heavy cream, stirring gently to combine. Cover and cook on high for 2-3 hours or low for 4-5 hours.
In a small bowl, whisk cornstarch with the remaining 2 tablespoons of chicken broth.
Stir the cornstarch mixture and gnocchi into the slow cooker. Cook for an additional 30-60 minutes, until the gnocchi is tender and the sauce has thickened.
Just before serving, stir in fresh spinach and an extra 1/2 cup Parmesan cheese. Serve warm and enjoy!