Chocolate and cherry cake

200g butter

200g dark chocolate, broken into small pieces

25ml strong coffee

75ml buttermilk

3 eggs

¼ tsp bread soda

85g plain flour

85g self-raising flour

190g brown sugar

180g caster sugar

25g cocoa powder

2 tsp Amarena cherries and 1 tbs of their syrup

To decorate: 

50g butter, softened

170g icing sugar

150g Mascarpone cheese

4 tbsp Amarena cherries