Cook grated pineapple and sugar in a heavy-based saucepan over medium heat until it starts to boil. Reduce the heat and add lemon juice. Simmer until mixture is dry, thick and paste-like. Leave to cool completely.
Divide pineapple paste into 35g each and roll into small balls. Divide lotus paste into 50g each. Wrap lotus paste around the pineapple paste balls.
To prepare pastry dough
Combine ingredients (A) in a bowl. Beat butter, icing sugar, egg and evaporated milk for about 1-2 minutes with an electric mixer. Add combined ingredients (A) and mix by hand to a soft dough. Cover the dough and leave aside for 10 minutes. Divide dough into balls of 40g each.
Lightly dust your hands with flour and roll out pastry with a rolling pin, making sure that the centre portion is slightly thicker and the edges are thinner.
Place rolled pastry dough over the prepared filling. Wrap up neatly. Shape into a dome and let them sit evenly on a lightly-greased baking tray, spacing them out neatly.
Brush the mooncakes with egg glaze and sprinkle them with a little of the combined sesame seeds.