How to Make It
In a saucepan, heat lemon juice and light brown sugar over medium heat until sugar dissolves. Let cool if you have time (if not, just proceed), then combine in a large pitcher or jar with bourbon, unfiltered apple cider, Calvados, and bitters. Just before serving, thinly slice an apple and float on the top if you like, and set out with glasses and ice.
Make ahead: Cocktail without apple slices, up to 1 week, chilled; up to 3 months, frozen (if you use
a glass jar, fill to 2 inches below
lid so it won’t explode).