Pulse 24 Oreo cookies in a food processor until fine crumbs. Melt 5 tablespoons of unsalted butter and combine with cookie crumbs.

Press the mixture into a 9-inch pie plate and chill for 10 minutes.

In a saucepan, bring 1/2 cup of milk to a gentle simmer. Stir in 2 cups of marshmallows until melted and smooth.

Cool for 15 minutes, then refrigerate to chill further.

Stir in 1 teaspoon peppermint extract and 1 teaspoon vanilla extract. Add green gel food dye if desired.

In another bowl, whip 1 cup of heavy cream to stiff peaks. Fold into the chilled marshmallow mixture.

Spread the mixture into the crust, cover, and freeze for at least 3 hours to set.

Garnish with whipped cream and chopped Andes mints or crushed Oreos before serving.