Prepare the Zucchini: Wash zucchinis, grate them, and squeeze out excess moisture.
Mix Dry Ingredients: Combine flour, baking powder, baking soda, garlic powder, onion powder, black pepper, and salt in a bowl.
Combine Wet Ingredients: Whisk eggs, then add milk and olive oil; mix well.
Combine Wet and Dry Mixtures: Fold wet ingredients into dry until just combined.
Incorporate Cheese and Zucchini: Fold in grated zucchini, Parmesan, and mozzarella.
Bake Your Muffins: Preheat oven to 375°F, fill muffin cups, sprinkle breadcrumbs, and bake for 20-25 minutes.