In a medium saucepan combine all three ingredients. Heat over medium-low heat for 7-10 minutes. Stirring every few minutes to avoid splatter.
Preheat oven to 350 degrees. Prep 9x13 baking dish with lining with parchment paper.
Place the carrots, spinach, onion and garlic in food processor and process for 1-2 minutes or until everything is in very small pieces.
Mix all ingredients together in a large mixing bowl.
Scoop out a small handful of mixture (golf-ball sized) and roll into a ball. Place in the prepared baking dish.
Bake in the oven for 35-45 minutes or until meatballs are cooked through.