Step 1

Line a 7 cm x 25 cm bar tin with baking paper.

Step 2

Melt butter in a medium saucepan over a low heat. Add condensed milk, golden syrup and brown sugar.

Step 3

Stir over a low heat until it comes to the boil, then simmer for 10 minutes, stirring constantly.

Step 4

Remove from heat, stir in white chocolate and mix until smooth.

Step 5

Pour into prepared tin and allow to cool. Refrigerate for at least two hours. Serve cut into squares or slices.