- 1 cup (135g) plain flour
- ¼ cup (45g) self-raising flour
- ½ cup (75g) custard powder
- 175g unsalted butter, softened to room temperature
- 1 tsp vanilla extract
- ½ cup (60g) icing sugar mixture
- 1½ cups (185g) pure icing sugar
- 40g butter, softened to room temperature
- 2 tsp vanilla extract
- ½ tsp lemon juice
- Preheat oven to 200C (180C fan forced). Line two baking trays with baking paper.
- Place the flours and custard powder into the mixing bowl with the pouring shield, attach the flat beater to the stand mixer. Turn to speed 1 and mix for 1 minute to combine. Remove from the bowl and set aside.
- Place the butter, vanilla and icing sugar into the mixing bowl. Turn to speed 6 and beat for 3 minutes or until very light and fluffy, regularly wiping down the sides of the bowl with a spatula. Add the sifted flour mixture, turn to speed 1 and mix until just combined. Increase to speed 4 and mix until well combined and smooth.
- Roll a rounded teaspoon of the mixture into a ball and place onto prepared trays. Lightly press down with a fork. Repeat with the remaining mixture.
- Bake for 12 minutes on the centre shelf of the oven until lightly browned. Stand for 5 minutes before removing with a slide to a cooling rack. Allow biscuits to completely cool. Sandwich together with the filling.
- Attach the flat beater to the stand mixer. Beat the icing sugar and butter on speed 4 for 3 minutes or until light and fluffy. Add the vanilla and lemon juice. Beat on speed 1 until combined. Increase to speed 4 and beat for 2 minutes or until light and fluffy.
- Biscuits will keep for up to 5 days in an air tight container.