Mix together the red, yellow and blue food colouring, in the separate bowl to make brown if you do not have brown coloured food colouring.
In a large mixing bowl add the cream, butterscotch flavouring, vanilla extract (optional) and a few drops of the brown food colouring. Whip until you get soft peaks.
Add a few more drops at a time of the food colouring until you get the desired colour, while you are whipping the mixture.
Add the cold condensed milk and mix through until all combined.
In a container big enough to hold 2 litres (3.5 pints) of ice cream
Add a third of the ice cream on the bottom of the container, followed by 4 to 5 dollops of the caramel sauce. Repeat, making sure caramel is placed on top of the last layer of ice cream.
Swirl the caramel through the ice cream mixture, cover a place in the freezer for at least 2 hours before serving.