Stirred: +15 % of the pre-batch, +0.45 oz of water
Served
3 + 0.45 = 3.45 oz in the glass
Strength
1.28 ÷ 3.45 = 37.0 % ABV as served
Ethanol
1.28 oz × 29.57 ml × 0.789 g/ml = 30 g · about 208 kcal from the alcohol alone
IN THE GLASS
VANILLIN
FROM RYE · from oak barrel aging
Formula
C₈H₈O₃
Mass
152.15 g/mol
IUPAC
4-hydroxy-3-methoxybenzaldehyde
Bourbon's fingerprint, extracted from the charred American oak the law requires for aging. Same molecule as the vanilla bean's signature, so a well-aged bourbon legitimately tastes like vanilla. Chemistry, not metaphor. Cognac, aged rum, tequila reposado all extract vanillin from oak too. Different barrels, same molecule.
The apple-skin polyphenol, the molecule that gives hard cider its astringent backbone and tannic structure. Concentrated in skin and core, so cider pressed from whole apples carries far more than juice made from peeled fruit. Pharmacologically interesting too: phloridzin blocks intestinal glucose absorption, which is the mechanism modern SGLT2-inhibitor diabetes drugs took their inspiration from.
The bitter from gentian root, used across Campari, Aperol, sweet vermouth, Angostura, and most amari. Bitter compounds activate TAS2R taste receptors that evolved to detect plant alkaloids. The same machinery that makes broccoli taste bad to children also makes a Negroni taste like an adult ordered it.
Rye, applejack and Yellow Chartreuse: three spirits and no modifiers. Yellow Chartreuse (40% ABV, milder and sweeter than green) bridges the rye's oak with applejack's ester-forward apple notes. ABV lands near 38%. A sipping-strength stir.
PROVENANCE
First printed in Ted Saucier's 1951 Bottoms Up, credited to the Diamondback Lounge in Baltimore's Lord Baltimore Hotel, named for the local terrapin (Maryland's state reptile). Murray Stenson put it back on the menu at Seattle's Zig Zag Café around 2005, and the craft revival carried it from there. Three-spirit cocktails are notoriously unforgiving; change any proportion by a quarter ounce and the balance breaks.