Pre heat the oven to 160c.
Grease two 8" pan.
Beat sugar and butter till light and fluffy.
Add one egg at a time and beat well. Add 1 tbsp flour after each addition.
Fold in the remaining flour, vanilla essence and ganache.
Bake in the preheated oven for 25 to 30 minutes or till well risen.
Cool the cakes on wire rack and sandwich with reserved ganache cream.
Drape the chocolate icing over and sides of cake. Trim away the excess icing.
Divide the modeling icing into two. Knead red color into one modeling icing and shape into petals, overlapping one over the other.
Knead green color into other modeling icing and shape into leaves(use your thumb and fore finger to shape them).
Note: To prepare Ganache:
Put the grated chocolate in a mixing bowl. Simmer(do not boil) heavy cream in a thick bottomed pan and pour it over the grated chocolate. Whisk till thick. Cool it and fold into the cake batter.