Grease a bunt pan/cake pan of your choice (8 to 9 inches round) with melted butter and dust with flour. Set aside. Pre-heat oven to 160C (320F).
Place butter and sugar in a bowl and beat with an electric mixture until pale and fluffy for about 8 minutes. Add the eggs and beat well. Fold through the flour, baking powder and cocoa. Stir in the milk.
Spoon the mixture in the prepared tin and bake for 1 hour 10 minutes approximately until cooked through when tested in the centre with a skewer. Remove from the oven. Cool in the tin for 10 minutes and then gently turn onto a wire rack to cool.
To Make The Glaze
Place dark chocolate and cream in a heavy bottomed small saucepan over low heat, stirring until melted and smooth. Allow the mixture to stand for 10 minutes until thickened slightly.
Once the cake is completely cooled, pour the glaze over the cake. Cover and refrigerate cake or serve as is with the runny glaze.