In a stand mixer, combine 1 can of sweetened condensed milk, 1 teaspoon of peppermint extract, and 1 teaspoon of vanilla extract. Mix on low until combined, adding half of the powdered sugar until thick dough forms (2-3 minutes).

Turn mixture onto a floured surface, knead in remaining powdered sugar until dough is firm and not sticky (3-5 minutes). Roll to ½-inch thickness.

Cut circles from the rolled dough using a cookie cutter. If soft, chill in the freezer for 15 minutes. Place cutouts on parchment.

Transfer the baking sheet to the freezer for about 15 minutes to firm up the shapes.

Melt 8 ounces of dark chocolate in a microwave-safe bowl in 30-second increments, stirring frequently. Let cool slightly before dipping.

Dip each patty into melted chocolate using a fork, ensuring full coating. Allow excess to drip off before placing on parchment.

Refrigerate dipped patties for about 20 minutes to set chocolate coating.