1 For the muffins: heat the oven to 180°C (160° fan) 350°F gas 4. Grease a 10 hole muffin tin.
2 Beat the butter with an electric whisk until smooth. Gradually beat in the sugar and vanilla until very creamy.
3 Gradually beat in the eggs until blended.
4 Sift in the flour, cocoa and baking powder alternately with the milk and fold in gently until combined. Stir in the chocolate.
5 Spoon into the tins and bake for about 25 minutes until risen and firm to the touch. Cool in the tins for 5 minutes, then place on a wire rack to cool completely
6 Slice the top off each muffin and sprinkle the muffin with kirsch.
7 For the filling: whisk the cream until thick and lightly stir in the cherry jam, to give a marbled effect. Spoon the filling on each muffin and replace the tops.
8 Sift over a little icing sugar just before serving.