Fill a Collins glass with ice.
Pour 30ml Jägermeister over the ice.
Top with 120ml root beer, pouring slowly down the side of the glass to preserve carbonation.
Stir gently once or twice to combine without losing fizz.
Serve immediately.
The original recipe called for equal 30ml parts of each ingredient, which produces an overly spirit-forward drink with little room for the root beer's carbonation and sweetness to shine - a 1:4 ratio (30ml Jäger to 120ml root beer) is the sweet spot, mimicking the balance of a classic spirit-and-mixer highball.
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