Mix the cocoa powder, sugar, and flour together and place in a mixing bowl. Slowly whisk in the milk to first form a paste and later to dissolve the dry ingredients into the milk. Place milk mixture into a large saucepan and, stirring constantly over medium heat, slowly bring to a boil. Remove from heat, add chocolate, vanilla, and cinnamon, and stir to mix well and to melt chocolate. Fill the ramekins to 4/5 full, and allow to cool. Sprinkle each with toasted pine nuts and serve.