Tantalus Cocktail is a forbidden-fruit liqueur, brandy, and lemon drink from the late Harry of Ciro seam.
Harry of Ciro's ABC of Mixing Cocktails by Harry of Ciro's (1923, p.84) — Harry of Ciro's 1923
| 0.5 glass | lemon juice — Lemon Juice | acid |
| 0.5 glass | brandy | base |
| 0.5 glass | Forbidden Fruit — Forbidden Fruit Liqueur | base |
This matters because it preserves the forbidden-fruit liqueur lane in a simple early-1920s sour format.
Barflies and Cocktails by Harry McElhone and Wynn (1927, p.79) — Jack Bushby / Cecil Bar, Paris
| 0.33 part | lemon juice — Lemon Juice | acid |
| 0.33 part | brandy | base |
| 0.33 part | Forbidden Fruit — Forbidden Fruit Liqueur | base |
This matters because it preserves a compact late Paris citrus-and-fruit-liqueur branch with a named house attribution.
See also: Side-Car Cocktail, Valencia Cocktail