1. Preheat the oven to 350°F.
2. Break the chocolate into pieces and melt in a double boiler, stirring until smooth.
3. Beat the butter and sugar until light and fluffy. Add the eggs one at a time, beating after each addition.
4. Add the melted chocolate and mix. Pour in the milk and mix. Add the flour and baking powder, mixing slowly.
5. Pour the batter into small molds, filling them three-quarters full.
6. Bake for 18 minutes.
7. Remove from the oven and let cool on a rack. Cut the cakes in half.
8. In a small bowl, whip the cream cheese. Fill the interior of the cakes with it.
9. Place a tsp of blackberry jam in the center of each cake and close.
10. Decorate with a fresh blackberry held by a bamboo stick. Serve.