Begin by preparing the cookie dough. In a large bowl, sift together the flour, baking powder, and salt. Set aside.
In a stand mixer with the paddle attachment, cream together the vegetable shortening, sugar, eggs, and vanilla. Once combined, add half of the dry ingredients. Begin to mix and pour in the buttermilk. Then add the remaining dry ingredients and mix until just combined. Refrigerate the dough overnight or for at least four hours.
After the dough has chilled, preheat your oven to 375 degrees F.
On a well-floured surface, roll out about a quarter of the dough to a 1/4-inch thickness. Cut out the dough using a 3-inch circle cookie cutter. Transfer each cutout to an ungreased cookie sheet. Bake 8-10 minutes or until the first sign of browning appears on the surface of the cookies. Remove from the oven and transfer the cookies to a cutting board or your counter top to cool completely.
While the cookies cool, prepare your frosting*. With a mixer, cream together the vegetable shorting and butter. Slowly add the confectioners' sugar, one cup at a time. Mix in the vanilla extract. Add milk as needed for a smoother consistency. Thoroughly mix in the green food coloring to achieve the desired color.
Place the frosting in a piping bag with a "grass" tip.
Once your cookies have cooled, use the prepared piping bag to add "grass" to your cookies. Top with three chocolate eggs.
Allow the frosting to set before packing and storing the cookies in an airtight container.