Atonement

Select and pre-chill an Old Fashioned glass.

Prepare a garnish by twisting a strip of lemon zest.

Stir the straight rye whiskey, dark rum, blanc quinquina, Pedro Ximénez sherry, orgeat syrup, and Angostura bitters with ice until well chilled.

Strain the mixture into the prepared glass filled with fresh ice, ideally over a large cube or chunk of block ice.

Express the lemon zest twist over the cocktail to release its oils, then place it as a garnish.