Preheat the oven to 190ºC, gas mark 5.
Butter a 20cm springform tin and line the base with baking parchment. Butter the paper as well.
Put everything for the batter, except the marzipan, into a food processor, and blend until smooth.
Stir in the marzipan and scrape the batter into the cake tin.
Arrange the fruit on top, in a higgledy piggledy way, then sprinkle with the 2 tbsp caster sugar.
Bake for 1 hour 15 minutes, then test whether it's done by sticking a skewer into the middle of the cake. If it comes out with no batter clinging to it, the cake is ready. If not, cook for another 10 minutes and test again.
Leave in the tin for 10 minutes, then unclasp the ring around the cake and remove.
Leave to cool completely, then transfer the cake (peeling off the paper) to a serving plate.
Dust lightly with the icing sugar and serve with cream (whatever type you like).
