01 -
Stir together the sweetened condensed milk and peppermint extract in a large bowl. Gradually add powdered sugar, mixing until a stiff dough forms that you can knead with your hands.
02 -
Roll the dough into 1-inch balls and place on a parchment-lined baking sheet. Flatten each ball into a disc about 1/4 inch thick. Let dry uncovered at room temperature for 1 to 2 hours, flipping halfway through.
03 -
Slide the baking sheet into the freezer for 20 to 30 minutes so the patties firm up. Cold centers keep their shape when they hit warm chocolate.
04 -
Combine the chocolate chips and shortening in a microwave-safe bowl. Heat in 30-second bursts at 50 percent power, stirring between each, until smooth and glossy.
05 -
Drop one patty at a time into the chocolate. Flip with a fork, lift out, and tap the fork on the bowl edge to remove excess. Place back on parchment. Refrigerate for 30 minutes until the shell is hard.