Step 1

Preheat oven to 180C/160C fan forced. Grease a 10 x 20cm (base measurement) loaf pan and line with baking paper, allowing the paper to overhang the long sides.

Step 2

To make the custard, place the custard powder in a small saucepan. Add 1 tablespoon of milk and stir until smooth. Add the golden syrup and remaining milk. Cook, stirring, over medium-low heat for 2 minutes or until the mixture comes to the boil and thickens. Transfer to a bowl and set aside to cool, stirring occasionally.

Step 3

Use electric beaters to beat the butter and sugar in a medium bowl until pale and creamy. Beat in the golden syrup and vanilla. Add the eggs, 1 at a time, beating well after each addition, until combined. Add the flour and milk, alternating in small amounts, and beat until combined.

Step 4

Spoon two-thirds of the cake mixture into the prepared pan. Smooth the top. Dollop the custard over the cake mixture, then top with remaining mixture. Smooth the top. Bake for 40-45 minutes or until firm to touch. Cover loosely with foil if cake is browning too quickly.

Step 5

Set aside cake in pan for 10-15 minutes to cool and set firmly. Use the baking paper to transfer to a plate. Remove the paper. Serve warm with vanilla ice-cream, if using, or at room temperature. Drizzle with extra golden syrup.