I found this recipe on cocktailchemistrylab.com.

creme de cacao, creme de menthe, brandy, Fernet Branca, cream⁣
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This cocktail is made with the flavors in Thin Mint Girl Scout cookies. These cookies were originally called Chocolate Mints, and have been sold by Girl Scouts since the late 1940s. ⁣
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I was interested in giving this one a try because this is a fake martini recipe with serious ingredients! No cake flavored vodka or vanilla coffee creamer or rainbow sprinkles. Brandy and Fernet Branca elevate it, and even though it is flavored after a cookie, it doesn’t seem like a silly drink.⁣
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And yes, it’s very good. The brandy and Fernet give complexity to the flavor. My first time ever trying creme de menthe, too. ⁣