This spiced sponge, layered with fruit compote and cardamom buttercream, is topped with a golden pear.
Heat the oven to 190°C/170°C fan/375°F/Gas 5. Put the pears into one bowl, and 100g each of the blackcurrants and blueberries and all of the blackberries into another. Toss each bowl of fruit in 1 tablespoon of flour.
Beat together the butter and 375g of the sugar in a stand mixer until creamy. Gradually add the egg, beating after each addition and, on the fourth or fifth addition, add a tablespoon of the flour. Mix in the cinnamon and cardamom. Sift the remaining flour and the baking powder into the bowl and fold in. Divide the mixture into 3 equal portions.
Take one third of 1 portion of the sponge mixture and spread it evenly over the base of 1 prepared tin. Scatter over one sixth of the pear slices, then one sixth of the berry mixture. Spread half the remaining sponge mixture from the same portion over the fruit. Add another fruit layer on top, then the rest of the portion of batter. Repeat twice with the remaining tins and bowls of sponge mixture.
Bake the cakes for 50–55 minutes, until golden, springy, and a skewer inserted into the centres comes out clean. Loosen the sponges, then unclip the tins and leave to cool on a wire rack.
Make the compote. Put the remaining 150g blackcurrants, 150g blueberries and 60g sugar, along with the lemon juice and 1 tablespoon of water into a pan over a low heat and simmer, stirring, until the juices run. Increase the heat and boil for a few minutes, until thick. Leave to cool.
Make the icing. Beat the butter in a bowl until creamy, then add half of the icing sugar, the milk, cardamom and vanilla, and finally the remaining icing sugar. Beat for 2–3 minutes, until light and spreadable. Add more milk, a little at a time, if needed.
Gild the pear. Mix 1 teaspoon of icing sugar with a few drops of water to make a paste and brush this onto one side of the pear. Carefully, place the sheet of gold leaf onto the pear and press it gently with a dry paintbrush.
To assemble, place 1 sponge (top-side down) on a cake board. Spread with a quarter of the buttercream. Drizzle over 3 rounded tablespoons of the compote, then place the second sponge on top. Repeat, then place the third sponge on top (top-side up). Swirl the remaining buttercream over the top sponge. Decorate with berries and the gilded pear.