Ingredients

• 125g butter, chopped
• 1 cup dark brown sugar
• 1/2 cup treacle
• 1 teaspoon bicarbonate of soda
• 1 egg, lightly beaten
• 2 cups plain flour
• 1 tablespoon ground ginger
• 1 teaspoon ground allspice
• Christmas sprinkles, to decorate

Lemon frosting

• 4 cups icing sugar mixture
• 100g butter, softened
• 2 tablespoons milk
• 2 tablespoons lemon juice

Method

• Step 1 Place butter, sugar and treacle in a saucepan over medium-low heat. Cook, stirring occasionally, for 5 minutes or until mixture is melted and smooth. Bring to the boil. Remove from heat. Stir in bicarbonate of soda. Stand for 10 minutes to cool.
• Step 2 Preheat oven to 180C/160C fan-forced. Grease a 20cm x 30cm lamington pan. Line base and sides with baking paper, extending paper 5cm above edges of pan on all sides.
• Step 3 Transfer treacle mixture to a large heatproof bowl. Add egg. Stir to combine. Sift over flour, ginger and allspice. Stir until well combined. Spoon mixture into prepared pan, spreading evenly. Bake for 20 to 25 minutes or until just firm to touch. Cool completely in pan.
• Step 4 Make Lemon Frosting: Sift icing sugar into a large bowl. Add butter, milk and lemon juice. Beat with a wooden spoon for 1 minute or until mixture is thick and creamy. Spread frosting over cold slice. Decorate with sprinkles. Stand for 20 minutes to allow icing to firm up slightly. Cut into squares. Serve.