Step 1

Preheat oven to 400° F. Line baking sheets with parchment paper and set aside.

Step 2

In a bowl, whisk together the flour, baking powder, and salt. Set aside.

Step 3

In the bowl of a stand mixer fitted with a paddle attachment, cream together softened butter and confectioners' sugar. Add the egg and vanilla, and beat until thoroughly incorporated. Scrape down sides as necessary.

Step 4

With mixer on low, slowly add flour mixture to the bowl. The dough is ready when most of it sticks to the paddle. When touched it, it has a little give, but does not stick to fingers.

Step 5

Flour the work surface and roll dough to about 1/4 inch thick, using flour for dusting as necessary. Use a shamrock cookie cutter to cut out cookies. Place cookies on prepared baking sheet and bake for 7 to 8 minutes, or until the edges start to turn golden. Transfer cookies to a wire rack to cool completely. Gather up scraps and reroll dough. Repeat until no dough remains.

Step 6

In a double boiler (or a makeshift one), melt chocolate with shortening (see tips for melting chocolate here). Dip half of the cookie in the chocolate and place on a wire rack set over a cookie sheet (to catch the drips and sprinkles). Immediately add the green sprinkles on the chocolate. Wait for chocolate to set and then enjoy!