Preheat oven to 180 C / Gas 4. Grease and flour two 23cm (9 in) round cake tins; cover bottoms with baking parchment.
In a large bowl, combine flour, 400g sugar, cocoa, baking powder, bicarb and salt. Add eggs, milk, oil; beat until well blended. Pour cake mixture into prepared tins.

Bake for 35 minutes or until cooked. Remove and cool completely.
To make the cherry filling: Drain cherries, reserving 125ml juice. Combine reserved juice, cherries, 200g sugar and cornflour in a 2 litre saucepan. Cook over low heat until thickened, stirring constantly. Cool before using.

To make the icing: Combine whipping cream and icing sugar in a chilled bowl. Beat with an electric mixer at high speed until stiff peaks form.
Reserve 1/4 of the whipped cream icing for decorating cake; set aside.

To assemble: Place one cake layer on cake plate. Pour the Kirsch through out the layers. Spread with whipped cream icing, then top with 180ml cherry topping. Top with second cake layer. Ice side of cake with chocolate butter icing. Spoon reserved icing into pastry bag fitted with star tip. Pipe around top and bottom edges of cake. Spoon remaining cherry topping onto top of cake.