Heat the oven to 200°C (180°C in a fan oven), 400°F, gas 6.
To make the cake mixture, mix the butter and the sugar until fluffy and add the eggs one after the other. Mix together the flour and then baking powder, stir in the almonds and mix the dry ingredients into the wet ones.
Add flood colouring to the cake mixture until it is bright green, then stir in the pineapple pieces. Line the cake tin with grease-proof paper and grease the sides. Pour the mixture into the tin and bake in the middle of the oven for 50-60 minutes. If the cake browns too quickly cover with aluminium foil. Remove from the oven, take the cake out of the tin and leave it too cool on a wire rack. Turn the oven down to 180°C (160°C in a fan oven), 375°F, gas.
To make the shortbread base, sieve the flour on the work surface and create a well in the middle. Place the butter in the well, add the sugar and a pinch of salt and quickly knead everything together to make a smooth dough. Wrap in clingfilm and chill for 1 hour.
Roll out the dough on a floured worksurface to make a round approx. 24 cm Ø. Place on a baking tray, pierce with a fork and bake until light brown (approx. 10 mins). Leave to cool.
Place the base on a cake plate and spread with the pineapple jam. Place the cake on top and push downly gently but firmly.
To make the marzipan coating, sieve the icing sugar and knead into the marzipan along with the rum. Heat the pineapple jam, bring to the boil and then puree. Spread it all over the sides of the cake.
Dust the work surface with icing sugar and roll out the marzipan into a large circle approx. 2-3 mm thick. Place it on top of the cake and press down gently but firmly. Cut the marzipan along the bottom edge of the cake and discard any leftovers. Place the cake on a wire rack on a baking tray.
Roll out the red and the green marzipan on a dusted work surface and cut out shooting star shapes. Mix together the egg white and the icing sugar until smooth. Fill the icing sugar into a piping bag and pipe a little blob onto each star. Stick a sliver ball on each star on top of the icing sugar and leave to dry.
Dissolve the chocolate with the palm fat and cover the cake with it. Leave to dry and then stick on the stars. Use the remaining icing sugar to drawn a picture on top of the cake. Then if desired sprinkle with icing sugar.