Which ingredient in a Pink Squirrel contributes a chocolate flavor?

In a Pink Squirrel cocktail, the ingredient that contributes a chocolate flavor is crème de cacao. This liqueur is specifically made from cocoa beans and has a distinctive chocolate profile that is integral to the drink's taste. While the Pink Squirrel is a creamy, dessert-like cocktail that can include various rich ingredients, the presence of crème de cacao is essential for imparting that chocolate essence.

The other ingredients play different roles: crème de almond adds a nutty flavor, vodka serves primarily as a neutral spirit without a distinct flavor contribution in this context, and heavy cream adds texture and richness but does not contribute any chocolate notes. Thus, the correct identification of crème de cacao as the source of chocolate flavor solidifies its importance in crafting the signature taste of a Pink Squirrel cocktail.