Apple Cake with Rum Buttercream

You will need: 2x 20.5cm deep sandwich tins, greased and base-lined.

1. Heat your oven to 180°C/350°F/gas 4. Put the soft butter and sugar into a large mixing bowl and beat for about 2 minutes with an electric mixer until thoroughly combined. Scrape down the sides of the bowl from time to time.

2. Beat the eggs with the vanilla in a small bowl with a fork, just until mixed. Gradually add to the butter mixture, beating well after each addition and scraping down the sides of the bowl as before.

3. Sift the flour, baking powder, bicarbonate of soda, cinnamon, ginger and nutmeg into another bowl. Add about a third of the flour mix to the egg mix and use a large metal spoon or plastic spatula to stir in gently. Then add about a third of the buttermilk and gently mix it in. Add the remaining flour and buttermilk in the same way, in 2 batches each. Add the apple, raisins and nuts to the bowl and gently stir in until everything is thoroughly combined.

4. Divide the mixture equally between the prepared tins and spread evenly. Place in the heated oven and bake for about 30 minutes until risen and golden brown and the top springs back when gently pressed in the centre.

5. Set the tins on a wire rack and run a rounded bladed knife around each sponge to loosen it from its tin. Turn out the sponges on to the rack and leave to cool completely.

6. To make the buttercream, put the sugar and water into a small heavy-based pan and heat gently, without boiling, until the sugar dissolves. Then bring the syrup to the boil and boil until the temperature reaches 110°C on a sugar thermometer (this will take about 5 minutes). Don’t let the syrup start to caramelise.

7. While the syrup is boiling, put the egg yolks into a heatproof bowl (set on a damp cloth to prevent wobbling) and whisk for a few seconds with an electric mixer until frothy. As soon as the syrup reaches the right temperature, slowly pour it into the bowl in a steady stream, whisking constantly. Then keep whisking until the mixture becomes very thick and mousse-like, pale in colour and completely cold.

8. Cut the butter into small pieces and gradually whisk into the egg mix, then whisk in the vanilla and rum to taste. The buttercream needs to be easy to spread but firm enough to hold its shape, so if necessary cover the bowl and chill briefly.

9. Set one sponge layer (crust-side down) on a serving plate. Spread half of the buttercream over the surface, then place the second sponge (crustside up) on this. Cover the top of the sponge with the rest of the buttercream, swirling it with a palette knife or round-bladed knife. Leave, uncovered, at cool room temperature to firm up for a couple of hours before serving. Store in an airtight container in a cool spot (not the fridge) and eat within 4 days.