
Aguardiente ("firewater") is a broad name for distilled spirits across the Spanish- and Portuguese-speaking world. It is a family, not one product, made from cane, wine, grape pomace or fruit.
If you need a Cuban-style cane spirit, this is the closest swap at the exact same measure.
A gorgeous spirit distilled directly from fresh cane juice. It leaves a grassier, brighter mark.
Rhum agricole blanc
Steps up exactly like cachaça, bringing loud, fresh grassy cane notes.
Orujo
A last resort. This Spanish pomace spirit smells of grape skins, not cane. It noticeably changes the drink.
Colombian aguardiente
Won't work. It is an entirely different beast packed with heavy anise flavor.
The base depends on the region. Most of Latin America distills it from cane, and Colombian guaro is a cane distillate flavored with anise, at a mild 24–29%. In Spain and Portugal the word more often means a wine or pomace distillate, which can run over 50%.
Strong cane and pomace aguardientes keep like any spirit. Colombian aguardiente is different: sweetened and low in alcohol, it is not indefinitely stable. Keep it closed and cool, and finish an opened bottle within months.