Ingredients (Serves 8)
For the chocolate icing
Preheat the oven to 180°C, 350°F, Gas 4. Grease a deep, 20cm/8in round cake tin. Line the base with baking paper.
Sift the flour, cocoa and bicarbonate of soda into a large mixing bowl. Stir in the sugar.
Combine the buttermilk, eggs and softened butter, then pour into the dry ingredients. Beat with an electric whisk on slow speed for 3 minutes, until just combined, then increase the speed to high and beat for 3 minutes more, until the mixture is free of lumps and increased in volume. Spoon into the prepared tin and smooth the top.
Bake for 40-50 minutes, or until a skewer inserted into the centre of the cake comes out clean. Remove from the oven and leave in the tin for 15 minutes before turning out onto a wire rack to cool completely.
To make the chocolate icing, place the chocolate and butter in a heatproof bowl set over a pan of gently simmering water and leave to melt gently. Remove the bowl from the heat, gently stir the chocolate until smooth then spread it evenly over the top and sides of the cake. Before it sets, combine the toasted flaked almonds with the crumbled Maltesers and press over the top and sides of the cake. Serve cut in slices.