Begin by peeling and grating 600 g of potatoes, then soak them in a large bowl of cold, salted water for 15 minutes.

Heat 2 tablespoons of olive oil in a skillet over medium heat. Sauté 1 chopped green onion until softened, about 2–3 minutes.

Add in 150 g of baby spinach, seasoning with salt and pepper, and cook until wilted, roughly 2 minutes.

Next, mix in 200 g of sliced champignon mushrooms, along with 1 minced garlic clove, and sauté for about 8 minutes, until the mushrooms are golden brown.

Allow the filling to cool slightly.

In a large mixing bowl, combine the drained and squeezed potatoes with 80 g of mozzarella cheese, 2 large eggs, 2 tablespoons of chopped fresh parsley, and seasoning with salt, pepper, and 1 teaspoon of dried oregano.

Stir this mixture until all ingredients are thoroughly combined, creating a sticky potato crust.

Preheat your oven to 200°C (390°F). Generously brush a 9-inch round baking dish with olive oil to prevent sticking.

Press the potato mixture into the dish, forming a crust that is about 2 inches high around the edges.

Bake the crust for 35-40 minutes, or until it turns golden brown and crispy.

Once the crust is baked and has cooled slightly, gently spoon the prepared mushroom and spinach filling into the center, spreading it evenly.

Top it off with the remaining 80 g of mozzarella cheese, 120 g of torn fior di latte, and 30 g of grated Parmesan.

Return the loaded pie to the preheated oven and bake for an additional 10-15 minutes, or until the cheese is melted and bubbly.

After baking, remove the pie from the oven and let it cool for about 5 minutes. Garnish with fresh parsley before serving warm.