Mix the milk with the sugar, the egg and the amidon in a pan that does not stick (Teflon) and let it boil for approximately 15 minutes, time in which it is constantly stirred.
After it is boiled, then add butter, the vanilla and the lemon rasping and continue to mix everything until homogenization.
Place the dough into a tray with a height of 4-5 cm. Place the hot filling between the layers.
