The Sidecar is a pre-Prohibition classic that features cognac, orange liqueur and fresh lemon juice. It has stood the test of time and remains in heavy rotation today at bars and in homes around the world. If you like the Sidecar, you should meet its lesser-known cousin, the Between the Sheets.

Conventional belief credits the cocktail to Harry’s New York Bar in Paris, where acclaimed bartender and author Harry MacElhone, supposedly created it in the 1920s. MacElhone has contributed several other classics to the boozy realm, including the White Lady and the Old Pal, so drinkers are forever in his debt.

The Between the Sheets starts as a Sidecar but diverges with a measure of light rum and skips the customary sugared rim. This two-spirit base lends complexity, merging the rich oak and fruit notes of cognac with the dry, tropical notes of light rum. Enlist high-quality bottles for each, but there’s no need to go overboard. Pick up a V.S. or V.S.O.P. cognac and an unaged or lightly aged rum, and you’ll be golden. A rich triple sec with some heft will round the edges of the spirits and provide a touch of bitter-orange sweetness.

As with most classic cocktails, slightly different versions of the original recipe have evolved over the years. This particular one comes from Allen Katz, the co-founder of New York Distilling Company and a leading expert on spirits and cocktails. He follows the classic Between the Sheets formula, combining equal parts rum, cognac and triple sec with a quarter-part fresh lemon juice for a potent drink—and that potency is likely the reason behind its provocative name. Some barkeeps prefer a bit more lemon for additional acidity, so customize the ratios to your liking. If you want to add flair, follow Katz’s lead and flame an orange peel over the surface of the cocktail for an aromatic hint of citrus oils.

Référence :
https://www.liquor.com/recipes/between-the-sheets/
https://www.diffordsguide.com/cocktails/recipe/209/between-the-sheets