Combine dark brown soft sugar, caster sugar, butter, golden syrup, cream, milk and vanilla in a medium saucepan over medium heat. Pour into a 20x20cm tin. Let cool before cutting into small squares.
Heat, stirring occasionally, to 121 to 129 degrees C, or until a small amount of syrup dropped into cold water forms a rigid ball.
Pour into a 20x20cm tin. Let cool before cutting into small squares.
Take each square of toffee and roll in the popping candy.