From Good Housekeeping; a lot of work, but worth it for a special occasion, and you can make the cake ahead and freeze it. I think you could use lime instead of orange; I love the combination of lime and white chocolate.
This makes a very large cake — at least a dozen servings. Reduce by half for a 15-cm tin; baking time will be the same.
6 large eggs, separated
250g golden caster sugar
150g self-raising flour
150g ground almonds
Grated zest of 2 oranges
100g golden granulated sugar
225 ml sweet white wine
Juice of 3 large oranges
225g good-quality white chocolate, chopped
400ml double cream
350g strawberries (sliced) or raspberries
Grease a deep 23cm cake tin and base-line it. Preheat oven to 180°C (160° fan oven).
Whisk the egg whites to soft peaks, then gradually beat in 50g caster sugar. Whisk until the mixture is glossy and stiff.
Whisk the egg yolks and the rest of the sugar in another bowl until pale and frothy. Stir in the flour to make a paste. Fold in a third of the egg white with a metal spoon. Then carefully but thoroughly fold in the remaining egg white, the almonds and the zest to make a smooth batter.
Spoon into the tin and bake for 35 minutes, testing with a skewer to see if it’s done. Cool in the tin for 10 minutes, then turn out onto a rack.
Put all the syrup ingredients in a small pan, heat gently till the sugar dissolves, then increase the heat and boil for 5 minutes, until syrupy. Set aside.
To make the ganache, put the chocolate and half the cream in a bowl and melt over simmering water (don’t stir!). Let it cool till it starts to thicken, then beat with a wooden spoon till cold and thick. Whip the remaining cream, stir a spoonful into the chocolate to loosen it, then fold in the rest. Cover and chill for 2 hours.
Cut the cake in half horizontally, pierce all over with a skewer, and put it, cut sides up, on a baking sheet with sides (so the syrup doesn’t run off). Spoon over the syrup and leave to soak in.
Spread a quarter of the ganache over the base and scatter most of the fruit over. Cover with the top half and press down lightly. Smooth the remaining ganache over the top and sides with a palette knife. Decorate with the remaining fruit just before serving