Final answer:
The key ingredient in a classic Mint Julep recipe is bourbon. This cocktail is a staple of Southern United States culture and is famously linked to the Kentucky Derby.b) Bourbon
Step-by-step explanation:
A classic Mint Julep recipe calls for bourbon as a key ingredient. This refreshing cocktail is traditionally associated with the Southern United States and is particularly famous for being the signature drink of the Kentucky Derby. To make a Mint Julep, you would muddle mint with sugar, then add the bourbon and fill the glass with crushed ice, garnishing it with more mint.