Put dates and almond milk into a blender, blend together until smooth.
Pour into a saucepan and bring to the boil. Reduce to a simmer, continue to cook whilst stirring over a low flame for 5-10 minutes, until thickened.
Remove from the heat, stir in the chocolate (or cocoa powder) until melted and incorporated.
Transfer to a sterilized glass jar. Serve warm, refrigerate and eat cold, or re-warm.