Pour 30ml Irish cream into the bottom of a shot glass.
Slowly pour 5ml Advocaat over the back of a bar spoon so it floats as the middle layer.
Slowly pour 30ml Sambuca over the back of a bar spoon so it floats on top.
To drink: insert a straw to the bottom and sip up the Irish cream first, then take the shot of the remaining layers, then inhale the lingering Sambuca vapors through the straw.
The layering works because of density differences: Irish cream is the heaviest, Advocaat sits in the middle, and Sambuca floats on top - pour each slowly over the back of a bar spoon to keep the layers clean and distinct.
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