Start by making the Golden Syrup filling to allow time for it to cool (or you can use Dulce de Leche to fill the cupcakes instead) .
Bring the water and syrup to a boil in a smallish saucepan, then turn off the heat and add the chocolate, swirling it around to melt in the hot liquid.
Leave it for a few minutes then whisk together.
Sieve in the icing sugar and whisk again until smooth.
Leave the syrup to cool until it thickens, you can put it in the fridge to finish cooling while you make the cupcakes.
Chop the chocolate into very small pieces and place in a heat proof bowl.
Heat the cream to just below boiling point and pour over the chopped chocolate. Let it stand for 5 minutes then whisk to mix.
Once the ganache has cooled use an electric whisk to whip air into it to make it lighter, and then spread over the cupcakes.
Any ganache you don’t use on the cupcakes can be made into truffles with a few drops of flavouring.
In a large mixing bowl, whisk together flour, cocoa, sugar, bicarbonate of soda, baking powder and salt.
Add the egg, milk, oil, vanilla and water - beat on low until smooth and combined, scraping down the sides as needed.
Evenly divide the batter between the wells of a 12 cup muffin tin lined with paper liners but no more than two-thirds full or they may overflow.
Place into the oven and bake until a toothpick placed in the centre of a cupcake comes out mostly clean with a few moist crumbs attached, about 18 to 24 minutes.
Remove from the oven and carefully turn cupcakes out onto a wire rack and allow to completely cool.
When cool, use either a cupcake corer or a knife to remove the centre of each cupcake (make sure you don’t go too far down). Take a small piece off the bottom of the core to allow room for the filling when you replace the top. Spoon a little of the Golden Syrup into the hole and replace the top.