Add whipping cream and sugar to a small bowl. Whip five minutes until a soft whipped cream forms, it's should be a pourable consistency.
If using espresso, pour hot water over both shots in a mug. If using a cup of coffee, pour it into a mug for serving.
Add cream on top of the coffee in the mug. Drizzle caramel on top of the cream, and stir to combine. Serve immediately.
To make the caramel, cook 2/3 of cup sugar with 3 tablespoons of butter in a heavy saucepan over high heat, stirring until amber-hued, 2 to 4 minutes. Stir in one cup of whipping cream (it'll bubble up). Cook, stirring until it boils. Keeps 1 month, chilled.