Schwarzwälder Kirschtorte

Step 1: Heat the oven to 350°F (325°F fan). Line the base of a 26 cm springform tin with baking paper; don't grease the sides.

Step 2: Whisk 6 eggs and 6 ½ oz caster sugar with an electric mixer on high for 8–10 minutes, until pale, very thick and tripled in volume; when you lift the whisk, the mixture should leave a trail that holds for a few seconds.

Step 3: Sift 3 ½ oz plain flour, 1 ¾ oz cornflour, 1 oz cocoa powder and 1 tsp baking powder over the eggs in two goes and fold in gently with a large spatula. Fold in 1 ¾ oz butter last. Pour into the tin.

Step 4: Bake for 30–35 minutes, until risen, springy when pressed and a skewer comes out clean. Run a knife round the edge, turn out upside down onto a rack and cool completely. Ideally leave overnight; it cuts more neatly.

Step 5: Drain 1 ½ lb jarred sour (Morello) cherries in juice, keeping the juice. Stir 2 tbsp cornflour with 4 tbsp of the juice. Heat 250 ml juice with 2 tbsp sugar in a pan, whisk in the cornflour mix and boil for 1 minute, stirring, until thick and clear. Fold in the cherries and cool completely.

Step 6: Cut the sponge horizontally into three even layers with a long serrated knife. Mix 6 tbsp of the remaining cherry juice with 4 tbsp kirsch (cherry brandy) (or use juice alone).

Step 7: Whip 3 ¼ cups double or whipping cream, 5 ½ oz mascarpone, 2 ⅛ oz icing sugar and 1 tsp vanilla extract until it holds firm peaks. Stop as soon as it does; a common mistake is over-whipping, which makes grainy cream that won't spread.

Step 8: Put the bottom layer on a plate inside the clean springform ring. Drizzle with a third of the cherry syrup, spread with a thin layer of cream, then pipe or spoon 3 rings of cream and fill the gaps with the cherry filling.

Step 9: Add the second layer, drizzle with syrup and spread with a thick layer of cream (about a quarter of it). Top with the last layer, cut side down, and drizzle with the rest of the syrup. Chill for 30 minutes.

Step 10: Remove the ring. Cover the top and sides with most of the remaining cream, smoothing it with a palette knife. Pipe 12 rosettes around the top edge with the rest.

Step 11: Shave 3 ½ oz dark chocolate with a vegetable peeler into curls and press them onto the sides and the middle of the top. Put a cherry from 12 fresh or cocktail cherries on each rosette. Chill for at least 4 hours before cutting with a knife dipped in hot water.