Italian Plum & Almond Cake

Ingredients

• 180g/60z butter at room temperature, plus extra for greasing
• 1 cup sugar
• 1 tsp vanilla extract
• finely grated zest of 2 lemons
• 3 large eggs at room temperature
• 1 1/2 cups ground almonds
• 1 cup self-raising flour
• 2 tbsp plain yoghurt or buttermilk
• 8 large semi-firm plums plums halved, stones removed
• 1 tbsp amaretto (optional)
• 2 tsp icing sugar to garnish