Method

• 1.
  Preheat oven to 160°C. Line base and side of a 22cm round cake pan.
• 2.
  Place citrus in a large saucepan with water and bring to the boil over high heat.
• 3.
  Reduce heat to a simmer and cook for 2 hours, topping up water as needed, then remove from the pan and cool slightly.
• 4.
  Cut in half and remove and discard seeds. Place citrus in a food processor and whiz into a puree then set aside to cool.
• 5.
  Place citrus and remaining ingredients, except icing sugar, in a bowl and whisk to combine. Pour mixture into prepared pan and bake for 1 hour 40 minutes or until the centre has levelled and springs back when gently pressed. Turn out onto a wire rack to cool.
• 6.
  For the lemon curd ice cream, place all ingredients in a bowl and whisk to combined. Place bowl over a saucepan of simmering water, stirring continuously, until it reaches 85°C or until a thick custard. Transfer to shallow tray, cover and chill in the fridge for 30 minutes or until cool. Place the mixture in an ice cream machine and churn for 60 minutes until it reaches desired consistency. Transfer to a loaf pan, cover surface directly with baking paper, then cover with plastic wrap and freeze for 6 hours to overnight or until firm.
• 7.
  Dust citrus cake with icing sugar and serve with lemon curd ice cream.