Place the biscuits until they fill the sides of the dish. Cook the gradients with milk and mix them with mixer. Put one layer of pistachio and one layer of biscuits in between. Cover it with plastic wrap. Rest them in the fridge for two hours. Turn the service plate upside down and heat the chocolate sauce to spread on the mix. Mix egg white, sugar and drops of lemon until they look like snow. Heat them in 150 degree oven for 25 minutes. Garnish the pie with paste and spread powder cacao on top. Feeling hungry? Enjoy!