Orange Bitters No. 6 by Regans'

Regans' has an intensely concentrated orange peel character with a distinctive cardamom backbone that cuts through spirit-forward cocktails. It was created by cocktail historian Gary Regan to fill a gap in the market and quickly became the professional bartender's standard orange bitter.

Regans' is more assertive and cardamom-forward, while Angostura Orange is sweeter and more approachable. Regans' stands up better in spirit-forward drinks like the Martini. Angostura Orange blends more gently in lighter cocktails. Many bars stock both.

Any orange bitters will work: Angostura Orange is softer and juicier, Fee Brothers West Indian leans candied and sweet. A classic bartender trick is blending Regans' and Fee Brothers half-and-half to get both the spice and the candied citrus in one dasher bottle.