A ginger cake coated in meringue and filled with spiced lemon curd – irresistible! You can make the sponges and the lemon curd up to three days in advance of assembling the cake. Once you’ve assembled and decorated the cake, though, eat within a day.
Preheat the oven to 180°C/160°C fan/350°F/Gas 4.
Make the sponge. In a medium pan, heat the butter, sugar, treacle, golden syrup and grated ginger on medium heat, until the sugar dissolves. Pour the mixture into the bowl of a stand mixer fitted with the beater attachment and allow it to cool for 2 minutes.
Add the eggs and ground spices to the bowl. Stir in the flour, bicarbonate of soda and baking powder. Finally, beat in the milk, until combined. Pour the mixture equally into the prepared tins and bake for 20–25 minutes, until just firm to the touch. Turn out onto a wire rack to cool.
Make the lemon curd. Grate the zest of 3 lemons and squeeze the juice of all 5. Place the zest and juice in a small pan and add the gelatine. Leave the gelatine to soften for 5 minutes, then add the sugar, and the grated and ground gingers.
Beat the whole eggs and the yolks together, then stir the mixture into the pan. Heat over a very low heat for 5–7 minutes, stirring continuously, until the mixture thickens (don’t let it scramble). Remove the pan from the heat and add the butter, a cube at a time, until melted. Pour the mixture into a bowl and chill for about 1 hour, until thickened and soft set.
Make the candied lemon. Pour 50ml of water into a small pan, add the sugar and the thinly sliced lemons and place over a medium heat. Bring to the boil, then lower the heat and simmer for 5 minutes, until the lemon peels are translucent.
Remove the pan from the heat and pour the syrup through a sieve into a bowl, catching the lemon slices in the sieve. Reserve the syrup, then transfer the lemon slices to a wire rack to drain completely. Reserve 3 or 4 whole slices and snip the remainder into little pieces.
When you’re ready to assemble the cake, make the meringue. Heat the syrup from the candied lemon in a small pan over a high heat. As soon as it reaches 110°C on a sugar thermometer, put the egg whites in the bowl of a stand mixer fitted with the whisk attachment. Whisk on a high speed to soft peaks.
When the syrup reaches 118°C, with the whisk still running, slowly add it to the egg whites in a continuous stream, until the meringue is thick, glossy, and stands in stiff peaks.
To assemble, spread the lemon curd over one of the sponges. Sprinkle with half the chopped candied lemon, then top with a second sponge. Spread with the remaining curd and sprinkle with the remaining lemon and top with the third sponge, placing that sponge top-side downwards.
Place 6 tablespoons of the meringue in the medium disposable piping bag. Use a palette knife to spread the remaining meringue over the top and sides of the stacked sponges.
Snip the end of the piping bag to make a 1cm hole. Pipe small blobs of meringue in 2 or 3 rows around half the top of the cake. Use a kitchen blow torch to lightly brown the meringue in places.
To finish, melt the chocolate in a small bowl suspended over a pan of simmering water (or use a microwave). Half dip the reserved candied lemon slices in the chocolate, and place them on a sheet of baking paper in the fridge to set (about 5 minutes). Position them like wheels in the meringue topping.