Preheat oven to 400° F. Spray a baking sheet with cooking spray and set aside.
Add broccoli, onion, carrot, spinach and mushrooms to a food processor and blend until well chopped.
Add ground turkey, the processed veggies, bread crumbs, egg, and spices to a large bowl. Mix until well combined (it may be easiest to use your hands.)
Shape mixture into meatballs (12-18 depending on preferred size) and arrange on prepared baking sheet.
Bake for about 15 minutes until cooked through and slightly browned.
Serve with spaghetti/marinara sauce for dipping.