Mix all ingredients for the dough. Bake on the tray for about 20 minutes at approx. 180 ° C top / bottom heat (make a cooking test!).
Knead the marzipan with the green food color (if necessary mix in a little blue food color so that the green shade becomes a little darker). Roll out into a rectangle (slightly smaller than the cake). When the cake has cooled completely, place the green plate on top.
Make a frosting with powdered sugar and a little water and decorate accordingly with the piping bag. Possibly color the frosting with a different food color for further decorations. From e.g., Cut bacon `chalk`. Mount the sponge, etc.