Trim the mushrooms and chop them roughly. Dice Fontina PDO, removing the rind, and keep it aside.
Fry a chopped shallot in a frying pan with a little extra virgin olive oil. Add the mushrooms and cook for a few minutes. Add the marjoram leaves and season with salt and pepper.
Ina bowl, Mix the eggs with fresh cream, and add the cooked mushrooms. Add salt and pepper to taste and set the mixture aside.
Spread the phyllo pastry sheets on a 24/26 cm baking dish, oiling each layer with the help of a kitchen brush. Once the layers finished, pour the egg and mushroom mixture and the diced Fontina PDO in the middle.
Bake in a preheated oven at 180°C for 15 minutes and then at 160°C for another 15 minutes. Serve warm.