2 Tbsp custard powder
1 cup caster sugar
1 cup milk
200g butter, at room temperature
3 tsp vanilla extract
Extra butter, melted, for greasing
2 eggs, whisked
2 1/2 cups self-raising flour, sifted
1/2 cup buttermilk
2 (400g) pears, cored, quartered, diced
Icing sugar mixture, for dusting
Combine custard powder and 1/4 cup of the sugar in a small saucepan. Slowly add milk, stirring until combined. Put over a medium heat and cook, stirring constantly, until mixture comes to the boil and thickens. Remove from heat. Stir in 20g of the butter and 2 tsp of the vanilla. Transfer to a bowl. Cool.
Preheat oven to 180°C. Grease a 30 x 20cm lamington tin with extra melted butter and line with baking paper. Put remaining sugar, butter and vanilla in a large bowl and beat, using an electric mixer, until light and creamy. Add eggs, 1 at a time, beating well after each addition. Using a large metal spoon, gently fold in flour and buttermilk until well combined. Add pear and stir until combined.
Spoon 1/2 the batter into prepared tin, then spread cooled custard on top. Spoon remaining batter over custard, spreading evenly. Bake for 45 minutes or until cooked when tested with a skewer.
Cool in tin for 10 minutes, then transfer to a wire rack to cool completely. Dust with icing sugar. Cut into squares to serve.