1
["Make the ""butter"": Add 1/2 stick of the unsalted butter to a medium pot. Turn the heat to medium, and let the butter melt. Whisk in: the dark brown sugar, 1/2 cup of the heavy cream, and the flaky sea salt. Let the mixture come to a mild boil for about 5 minutes, whisking as you go. When the butterscotch is thick enough to really coat the back of a spoon, remove it from the heat. Stir in the vanilla extract. If you like, add a bit more sea salt and vanilla to taste.", "Make the ""foam"": Pour 1 cup of the heavy cream into a bowl. If you have an electric mixture, break it out now. Mix the cream until it's whipped to your liking.", "Put the drink together: Melt the remaining butter in a medium pot, over medium-low heat. Add the grated ginger, the nutmeg, the light brown sugar, and the vanilla bean. Stir to combine. Wait until the butter is bubbling gently, and then add the rum and stir again. Let the rum come to a little bubble, 1 minute.", "Add the ginger beer to the pot, and lower the heat a tad. Keep the pot on the stove just long enough for the ginger beer to heat through, and to impart the flavor of the ginger and vanilla, about 3-4 minutes.", "Prepare your glasses. Add a spoonful of butterscotch to the bottom of each glass (adjust depending on personal sweetness preferences).", "Run the butterbeer through a fine seive or cheesecloth, to remove any ginger bits, and the vanilla bean.", "Fill each glass 2/3 full with the strained butterbeer. Top with the whipped cream, and a gentle dusting of nutmeg. Serve warm. (If left to cool, the butterbeer will separate a little; you can fix this by reheating and stirring.)"]
