The Tender Knob comes from bartending icon H. Joseph Ehrmann. Ehrmann is the owner of Elixir, one of the oldest continually operating taverns in San Francisco. It’s that very city that helps give the Tender Knob its playful name—one area in town is named the Tendernob, a portmanteau to signify where the Tenderloin and Nob Hill neighborhoods intersect. The Tender Knob name is also a play on Knob Creek, the bourbon used in this lively cocktail. A lauded Kentucky bourbon, Knob Creek is a commendable whiskey both for using in high-end cocktails or for drinking straight, either neat or with a bit of ice to help mellow its intensity.

For the apple part of this autumnal drink, Ehrmann muddles apples directly into the shaker and uses a hard apple cider, which transforms the drink into a spritzy highball. These days, cideries are becoming nearly as ubiquitous as breweries. Though there are the big-name cider brands readily available in most markets, plenty of smaller producers are creating special ciders. A pure, unadulterated apple cider is the right pick for this drink.

Référence : https://www.liquor.com/recipes/the-tender-knob/