For the base
1/2 cup plain flour
1/4 cup self-raising flour
1/4 cup brown sugar
1 tablespoon cocoa powder
90g butter, melted
For the filling
200g white chocolate
2 cups plain flour
1/2 cup caster sugar
1/3 cup brown sugar
2 tablespoons golden syrup
400g Crunchie bars, chopped
1/4 cup vegetable oil
125g malt biscuits, crushed
Ice-cream to serve
To make the base, place plain flour, self-raising flour, brown sugar and cocoa powder into a medium bowl and stir to combine. Add butter and stir to combine.
Place mixture into a 20c,x20cm brownie tin which has been greased and lined with baking paper, pressing into corners with a spoon to create a level base. Place in 180-degree oven for 15 minutes. Cook and set aside.
To make the filling, n a large heat-proof bowl over a saucepan of water, which is simmering on heat, add butter and white chocolate and stir until chocolate is melted and mixture is combined.
Remove bowl from heat and add flour and eggs and stir to combine. Separate mixture evenly into two bowls. In one bowl, add caster sugar to the mixture and set aside. In the other bowl, add extra brown sugar and golden syrup and set aside.
Place 5 large spoonfuls of the brown sugar mixture to the cooked base - 4 spoonfuls in each corner and the last spoonful in the centre - leaving gaps in between. Place large spoonfuls of the caster sugar mixture into the gaps until all the mixtures are used up.
Place in a 160-degree oven for one hour. Cook and set aside.
Place Crunchie bars and vegetable oil into a medium bowl and microwave for 90 seconds, stirring every 30 seconds.
Place Crunchie mix on top of slice and smooth out. Top with crushed malt biscuits.
Slice into 9 pieces and top with ice-cream to serve.