Rusty Nail

Choose a blended Scotch whisky with enough malt, oak and character to remain noticeable beside the liqueur. An extremely delicate whisky can disappear, while a very smoky Scotch will produce a considerably more intense variation.

For the honey liqueur, Drambuie is the classic choice. Its combination of aged Scotch whisky, heather honey, herbs and spices gives the Rusty Nail its characteristic sweetness and aromatic depth. drambuie.com

A fresh lemon twist provides aroma rather than acidity. Expressing the peel over the glass adds bright citrus oils that contrast with the darker whisky and honey flavours.

Too much can make the cocktail noticeably sweet and obscure the character of the Scotch. Using 40 ml Scotch and 20 ml Drambuie keeps the whisky prominent while still providing the honeyed character that distinguishes the drink. 

Dilution is equally important. Because there is no juice or mixer, a short stir with good ice softens the alcohol and integrates the two ingredients without making the drink watery.

The Rusty Nail became particularly associated with New York bar culture and the Rat Pack era of the 1960s. Drambuie's official history describes it as the most popular cocktail in the New York bars frequented by the Rat Pack during that period. 

Drambuie's own history stretches much further back. The brand traces its origins to an 18th-century recipe associated with Prince Charles Edward Stuart and the Isle of Skye. The name was later patented by James Ross in 1893, and the Drambuie Liqueur Company was established in 1914. drambuie.com

The combination of Scotch and Drambuie ultimately became one of the best-known two-ingredient whisky cocktails.

Build the cocktail directly in the serving glass.

Add the Scotch and Drambuie over good-quality ice and stir until the ingredients are combined, properly chilled and slightly diluted. Drambuie's official method similarly calls for pouring both ingredients over clear ice and stirring until chilled and diluted to taste. 

There is no need to shake the drink. Shaking would introduce unnecessary aeration and cloudiness into a cocktail that should remain clear and spirit-forward.

Keep the Scotch prominent. The 2:1 proportion gives Drambuie enough presence without allowing its sweetness to dominate the whisky.

Use good ice. Because the cocktail is served entirely over ice, large, solid cubes help keep it cold while controlling dilution.

Try a smokier Scotch. A moderately smoky whisky creates a deeper version with smoke playing against Drambuie's honey and herbs.

Adjust the sweetness. If you prefer a drier, more whisky-forward drink, slightly reduce the Drambuie rather than adding more ingredients.