Method

Preheat oven to 180°C (350°F).

1. Pattern the plums over the base of a lightly greased 24cm-round tin lined with non-stick baking paper to form two layers. Fill in the gaps with the blueberries.
2. Sprinkle with 110g sugar and set aside. Place the butter, remaining sugar, and lemon zest in an electric mixer and beat for 8–10 minutes or until pale and creamy.
3. Scrape down the sides of the bowl and add the eggs, one at a time, beating well after each addition. Add the flour, baking powder, bicarbonate of soda, ground almonds, vanilla extract and buttermilk and beat on low speed until just combined.
4. Spoon the mixture over the fruit and smooth the top with a palette knife. Bake for 45 minutes. Cover loosely with aluminium foil and bake for a further 40–45 minutes or until cooked when tested with a skewer.
5. Allow to cool in the tin at room temperature until just warm. Invert the cake onto a serving plate and carefully remove the tin to serve.