Apple Custard Tea Cakes

Ingredients

90g butter, softened
1/2 tsp vanilla extract
1/2 cup caster sugar
2 eggs
3/4 cup self-raising flour
1/4 cup custard powder
2 tbs milk
1 large apple, sliced thinly
30g butter, extra, melted
1 tbs caster sugar
1/2 tsp ground cinnamon
Custard Filling
1 tbs custard powder
1 tbs caster sugar
1/2 cup milk
1/4 tsp vanilla extract

Preheat oven to 180C. Line muffin pan with paper cases. Make the custard filling. Blend custard powder and sugar with milk and extract in a small saucepan. Stir over a low heat until mixture boils and thickens. Remove from heat, leave to cool to room temperature.
Beat butter, extract, sugar, eggs, flour and custard powder, then add milk in a bowl with an electric mixer until combined. Divide half the mixture among the paper cases, top with custard then remaining cake mixture. Spread mixture to cover custard. Top with apple, pressing slightly into cakes. Bake for about 30 minutes.
Turn hit cakes, top-side onto a wire rack. Brush hot cakes with extra butter, ten sprinkle with combined extra sugar and cinnamon. Serve warm or cold.