Preheat oven to 375°F (190°C) and line a muffin tin with liners or grease lightly.
Grate zucchini and squeeze out excess moisture using a clean towel.
In a bowl, whisk flour, baking powder, baking soda, salt, pepper, and garlic powder.
In another bowl, whisk eggs, milk, and oil until combined. Add zucchini and mix.
Add dry ingredients into wet ingredients and stir until just combined. Do not overmix.
Fold in Parmesan, mozzarella (if using), and herbs.
Spoon batter into muffin cups, filling ¾ full.
Sprinkle extra Parmesan on top for a crispy crust.
Bake for 18–22 minutes or until golden and set.
Cool slightly before serving warm.