125g unsalted butter, chopped, at room temperature
¾ cup caster sugar
2 teaspoons vanilla bean paste
½ cup milk
1 ¼ cups self-raising flour
¼ cup custard powder
½ cup thick vanilla custard
250g unsalted butter, chopped, at room temperature
1 2/3 cups icing sugar mixture
125g dark chocolate, melted, cooled
Line a 12-hole muffin pan (1/3-cup capacity) with paper cases.
Beat butter, sugar and vanilla in a small bowl of an electric mixer until light and fluffy. Beat in eggs, one at a time, until combined. Transfer to a large bowl.
Add milk and combined sifted flour and custard powder. Fold until combined. Divide evenly among paper cases.
Cook in a moderately slow oven (160C) for about 20 minutes, or until a skewer inserted into the centre comes out clean. Remove from oven. Stand in pan for 5 minutes. Transfer to a wire rack to cool completely.
To make chocolate frosting, beat butter in same, clean bowl of electric mixer until pale. Gradually add sugar, beating until smooth. Beat in chocolate until combined. Transfer to a piping bag fitted with an 11mm star nozzle.
To assemble, cut a 2cm deep circle from the top of each cake, leaving a ½cm border. Fill each hole with about 2 teaspoons custard. Pipe frosting over top.
TIP! Filled and decorated cupcakes can be made up to 1 hour ahead. Keep in an airtight container in the fridge. Try turning cupcake circles into crumbs and freeze to use later to make layered fruit parfaits or cake pops.