Beat foam eggs and sugar. Gradually add the sifted flour and baking powder. Pan to the bottom and sides of the baking dish or round pan with a diameter of 26 cm and sprinkle with flour. Pour the mixture and bake in a preheated oven at 160 C for 25 minutes. Then leave the base to cool completely at room temperature, but not removed from the vessel in which it is baked. frosting: In a saucepan pour the milk and to this was added cinnamon, vanilla and lemon zest. The mixture is boiled at neprekasvato stirring over low heat 5 minutes. Cooled, and then thereto a spoon by spoon with cream and mixed with a mixer until a smooth mixture. Spread glaze evenly over the base. Decorate with optional slices of oranges or other fruits in season.