Equal parts bourbon, Aperol, Amaro Nonino, and lemon — the modern classic that never fails.
Amaro Nonino Quintessentia is a grappa-based herbal liqueur from Friuli in northeast Italy. It's lighter, sweeter, and less aggressively bitter than most amari — which is exactly why it works here. A heavier amaro (like Averna or Montenegro) would overwhelm the bourbon and Aperol.
The closest substitute is Montenegro, which is sweeter. If you use it, reduce to ½ oz and add an extra ¼ oz bourbon. Do not use Campari, Fernet, or Cynar as substitutes — they're too intense and will wreck the balance.
Swap bourbon for mezcal. The smoke plays unusually well against the bitter Aperol — a more complex, adult version of an already complex drink.
Swap Aperol for Cappelletti (a wine-based aperitivo) and use white whiskey or unaged rum. Lighter and more floral.
Add ¼ oz grapefruit juice alongside the lemon. Brighter and more citrus-forward — good in summer.
Use rye whiskey instead of bourbon. The rye spice sharpens the drink and plays against the Aperol's sweetness in a different way.