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Icing
In a large measuring jug whisk together the vegetable oil, 150 ml / 5 fl oz water, the vanilla extract and vinegar. Sift the flour cocoa and bicarbonate of soda into a large bowl and stir in the salt and caster sugar. Gradually stir in the vinegar mixture until well combined taking care not to over-mix.
Divide the mixture between the muffin cases. Bake for 15-20 minutes until firm and springy to the touch. Allow to cool in the tin.
Meanwhile, melt the chocolate and margarine in a bowl set over a pan of simmering water. Spoon a thick layer over the surface of cupcakes and leave for 15-20 minutes until cool and set.
Makes 8.
posted by Mr Falafel