I have been struggling to understand how to make a reliable Chocolate Ganache icing which slides over a cake, leaving a shiny, smooth covering. And produces this effect –
Shirley O. Corriher and Harold McGee have come to the rescue! Apparently chocolate is a complex mix of particles and fats, and in making Chocolate Ganache the two important factors are heat and liquid.
To melt chocolate on its own break/chop into small pieces, heat gently until it starts melting (use the microwave), and then stir constantly until all the chocolate has melted.
To make a ganache, heat the chocolate together with sufficient liquid so that the particles are spread in the liquid. When the liquid is insufficient the cocoa and sugar particles are ‘glued’ together and the chocolate seizes. Or add all the liquid at once, or add the melted chocolate to the other ingredients, i.e. maintain a correct ratio between chocolate and liquid.
What is ‘sufficient liquid’? Shirley says 2 tablespoons liquid for 2 ozs unsweetened chocolate.
And the ganache? Shirley points to Sherry Yard, and her book The Secrets of Baking:
Soft ganache (for mouses, fillings, sauces) – two parts by weight double cream to one part by weight chocolate
Medium ganache (icings) – equal weights chocolate and double cream
Firm ganache (icings) – two parts by weight chocolate to one part by weight double cream
And the shine? Shirley adds corn syrup, but I think golden syrup would also work, or honey, although these are sweeter. However, she doesn’t give the ratio…
You may be interested in
A demonstration of Chocolate Ganache by Kitchen Kemistry
Satiny Chocolate Ganache with golden syrup
Ed Kimber‘s Ganache with golden syrup & butter (is this necessary?)
Chocolate, double cream & golden syrup recipe, and another one here
(The photograph of chocolate spoon at top of post is here.)