Find a recipe, either new or old, and switch around at least two of the ingredients to sister or cousin ingredients but holding the proportions and some of the ingredients the same. The new recipe should be recognizable as a morph of the old one when viewed side by side.
I knew right away that I wanted to use Harry Craddock’s Corpse Reviver No. 2 as my inspiration. Since it’s an equal-parts cocktail (with a rinse), I figured that it would be easy to experiment. In the past I had tried making subtle changes to ingredients in the CR2, evaluating the influence of using Cocchi Americano vs. Lillet or Cointreau vs. Pierre Ferrand dry curaçao, but I had never tried switching ingredients.
My first thought was to use a white rum instead of gin, but then I remembered the excellent Paddington from PDT. Although altering the original ratios, it is clearly based on the CR2 and cleverly switches Cointreau for a spoonful of orange marmalade. The Savoy Cocktail book also has the Culross which is rum based and uses apricot liqueur instead of Cointreau.
I considered using tequila for my CR2 variation, but soon realized that someone at Rickhouse already had the same brilliant idea (and with the original ratios too!) resulting in the Corpse Reviver No. 5 with tequila blanco, Cocchi Americano (instead of Lillet), pineapple gum syrup (instead of Cointreau), lemon juice and absinthe.
So tequila and rum were out. Moving on to dark spirits; cognac had been covered in the Hurly Burly (the other switch being Montenegro for the Cointreau), itself a riff on another Savoy cocktail the Hoop La! (aka Frank Sullivan cocktail) which is identical to the CR2 with cognac and no absinthe rinse. I finally settled on rye…
With rye as the base spirit, I decided to switch the Lillet for Bonal gentiane quina. Like Lillet, Bonal is a quinquina (a fortified aromatized aperitif wine with cinchona bark), although the quinine is much more pronounced compared to Lillet. Bonal being close to a vermouth, pairing it with rye made sense. For the other ingredients kept the lemon juice, I used dry curaçao instead of Cointreau and kept the rinse (I used pastis).
So here are the original and the twist side by side.