Put the sugar and water in a heavy based pan and heat gently, stirring until the sugar has dissolved. Raise the heat and cook without stirring until a rich, deep golden caramel is obtained. (If sugar crystals appear around the edge of the inside of the pan, use a pastry brush and water to brush away so the caramel doesn’t crystalise.) As soon as it starts to turn a deep brown, remove from the heat and pour in the thickened cream little by little and taking care that it doesn’t spit on you. Whisk until the caramel has dissolved into the cream and it stays together nice and thick. Let the caramel cool a little bit, then whisk in the butter a few cubes at a time until the sauce has a nice thick glossy appearance. Stir in the macadamias and cool completely. To Serve:
Cut a square of the Brownie and serve on a plate with a good dollop of the Macadamia Caramel!