Preheat oven to 400°F. Line a baking sheet with parchment paper or a silicone baking mat; set aside.

In a large bowl, combine ground chicken, Panko, egg, garlic and onion powder and green onions; season with salt and pepper, to taste. Using a wooden spoon or clean hands, stir until well combined. Roll the mixture into 1 1/4-to-1 1/2-inch meatballs, forming about 24 meatballs.

Place meatballs onto prepared baking sheet and bake for 4-5 minutes, or until all sides are browned.

Place meatballs into a slow cooker(Crock pot). Add buffalo sauce and gently toss to combine. Cover and cook on low heat for 2 hours.

Serve immediately, drizzled with ranch dressing, if desired.