Vanilla yoyo biscuits

Method

1. Preheat oven to 200C (180C fan forced). Line two baking trays with baking paper.
2. 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.
3. 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.
4. 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.
5. 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.
6. Filling
7. 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.