In a medium, heavy bottomed saucepan, stir the granulated sugar and water together over medium heat until the sugar has dissolved.

Once the mix comes to a simmer, stop stirring and watch carefully – once the sugar turns a deep amber and starts to smell ever so slightly smoky, turn off the heat and immediately add in the hot cream and salt.

Once the caramel stops bubbling, return to low heat and stir until smooth. Transfer to a heatproof bowl and let cool until room temperature and thickened to a thick, paste-like consistency, about 30 minutes.

In the bowl of a stand mixer fitted with a whisk attachment (or with a handheld electric mixer and large bowl) whip the butter on High speed until light and fluffy, about 5 minutes.

Add in the cooled caramel and continue whipping until incorporated.

Turn the mixer to low and gradually add in the powdered sugar a spoon at a time. Once the sugar is mixed in, turn the mixer up to High for another 2 minutes to fully aerate the frosting.

Store in a covered container at room temperature for up to one day, or refrigerate for up to 1 week.