It’s the hidden ingredient that’s the surprise. Mashed potato, often used in potato scones but even better in these small cakes – giving them a soft moist texture. I find frozen mashed potato works really well for this. For children you may like to leave the spice out, but I know a five-year-old who loves the subtle spiciness.
Begin by placing the chocolate, broken up, in a medium heatproof bowl, then add the condensed milk, sugar and butter.
Place this over a saucepan of barely simmering water, making sure the bowl does not touch the water. Then, keeping the heat at its lowest, leave everything to melt slowly, giving it the odd stir. It should take about 6 minutes for everything to combine and melt.
Meanwhile place the remaining cake ingredients in a large bowl and when the chocolate mixture is ready, add it to the rest and whisk it in until everything is smooth and creamy.
Now divide the mixture between the paper cases and bake them near the centre of the oven for about 15 minutes. After that allow them to cool in the tin, and while that’s happening make your chosen icing.
Just put the chocolate and condensed milk into another heatproof bowl and melt together (as above). Then take the bowl off the heat, stir in the butter until melted and allow the mixture to cool for about 5 minutes.
Using a small palette knife, spread the mixture over the top of the cakes and finish each one with two chocolate buttons.