In a small saucepan add the sugar and water and heat gently to melt sugar (DO NOT STIR).
Allow the mix to boil further, without stirring until sugar caramelizes. Keep an eye on the sugar as once the sugar starts to change colour, it will burn very quickly.
Allow the caramel to turn to a dark amber (slightly burnt caramel).
Immediately add the cream while sauce pan is off the heat and stir until mix is smooth.
Allow the caramel to cool to room temperature.
In a mixer bowl add the butter, icing sugar and salt and mix on med high speed until light and fluffy.
Add the caramel to the frosting and mix on med high for a few minutes until the caramel is mixed through.
The Icing can be refrigerated. However whisk it before use.
When you're ready to ice it, gently unroll the cake and remove the parchment paper.
Spread the icing on the cake surface and re roll the cake.
Transfer the cake onto a serving plate, seam side down and dust powdered sugar on top.