1. Preheat your oven to 180°C fan-forced.
2. Heat a drizzle of EVOO on a pan on medium-high heat and saute the onion and garlic, remove from heat and allow to cool.
3. Place the grated zucchini on a piece of paper towel or cheesecloth and squeeze out any excess juice.
In a large mixing bowl combine the grated zucchini, onion, garlic and remaining ingredients (except the passata) and use 4. your hands to mix until well combined.
5. Roll the mixture into equal size meatballs and place in an oven safe baking dish.
6. Pour the passata over the top, so all the meatballs are covered and bake in the oven for 25-30 minutes, or until cooked through.