Just grate the zucchini and potatoes! Nobody knows this delicious recipe!

Assemble the casserole:
Arrange half of the zucchini slices on the bottom of the prepared tray on top of the breadcrumbs. Spread the egg and potato mixture evenly over the zucchini layer.
Scatter the cooked onions and mushrooms over the potato mixture.
Sprinkle the grated mozzarella cheese evenly over the top.
Arrange the remaining zucchini slices on top of the cheese.
Sprinkle the remaining 40g of breadcrumbs over the top layer.

Bake:
Preheat your oven to 350°F (180°C).
Bake the casserole in the preheated oven for 45 minutes or until the top is golden and crispy.

To serve:
Let the casserole cool for a few minutes before slicing and serving.