In a large bowl, cream butter and sugar for 2-3 minutes with an electric mixer. Add eggs and peppermint extract and beat for 2-3 more minutes.

In a separate bowl, mix the flour, baking powder, and salt. Stir in the crushed peppermint candy. Add to the creamed butter mixture and mix until combined. Dough will be stiff.

Divide the dough in half. Line a baking sheet with a silicone baking mat or parchment paper. Roll each half into a rectangle that is about 12 inches by 2 ½ inches. Bake the two large rectangles on the baking sheet for about 25-30 minutes or just until golden brown. Transfer to wire racks and cool for 15 minutes.

Transfer the partially cooled rectangles to a cutting board and cut diagonally with a sharp knife into 1/2-inch slices. Bake for 12-15 minutes or until firm.

Transfer the slices to a wire rack to cool.

Place the chocolate chips and shortening in a microwave-safe bowl, and microwave for 30 seconds. Stir and then microwave for another 30 seconds. Stir until the mixture is smooth. Dip one end of each cookie in the chocolate and then roll in the crushed peppermint candy. Place on waxed paper until set. Store in an airtight container.