Sautee onions in a pan with butter. Add Speck Alto Adige PGI and sautee. Season with salt, pepper and chives. Preheat oven to 180 degrees Celsius. Mix eggs, milk and cream. Roll out Mille-Feuille-dough and put into buttered form. Add onion Speck Alto Adige PGI filling and the milk cream mix. Bake in an oven at 180 degrees Celsius for 20 minutes.