Step 1

Preheat oven to 180°C. Brush a deep, 20cm (base measurement) round cake pan with melted butter. Line the base with non-stick baking paper.

Step 2

Use an electric beater to beat the butter and sugar in a small bowl until pale and creamy. Add the eggs, 1 at a time, beating well after each addition. Beat in the vanilla. Transfer the mixture to a large bowl. Use a large metal spoon to fold in the combined flours, sour cream, orange rind and orange juice, in alternating batches. Stir until just smooth. Spoon the mixture into the prepared pan and smooth the surface. Bake for 50-55 minutes or until a skewer inserted into the centre comes out clean. Set aside in the pan to cool completely.

Step 3

To make the candied rind, place a wire rack over a baking tray. Place the orange rind in a small saucepan of boiling water for 10 seconds. Drain. Repeat. Stir the sugar and water in a saucepan over low heat until the sugar dissolves. Bring to the boil. Reduce heat to medium-low. Add the orange rind to the syrup. Simmer, without stirring, brushing down the side of the pan occasionally with a pastry brush dipped in water, for 5-10 minutes or until the rind is slightly transparent. Use tongs to transfer the rind to the wire rack to cool and harden.

Step 4

To make the orange icing, use a wooden spoon to beat the icing sugar, butter and orange juice in a heatproof bowl until smooth. Place the bowl over a small saucepan of simmering water. Stir until the icing is just warm. Set aside to cool slightly.

Step 5

Place the cake on a serving plate. Pour over the icing. Set aside until set. Decorate with the candied rind.