Melt butter in a microwave safe dish on high for 1 minute. Stir in sifted flour, sugar, cocoa, milk, egg and vanilla. Pour into 2.25L microwave safe container with lid. Combine extra sugar and cocoa, sprinkle over top of pudding. Pour over hot water. Cook covered on high for 8 minutes. Dust top with icing sugar (if desired, the pudding can be inverted).
Best served hot.
—Zamperoni Family