Ground the pistachios using a coffee grinder or food processor. Sift the pistachio powder with a sifter or mesh colander. In a medium bowl, whisk together the flour, baking powder and pistachio powder.
Sift the pudding mix using a sifter or mesh colander. In a large bowl, cream the butter, Crisco, pudding mix, sugar and food coloring until light and fluffy. Beat in the eggs one at a time, making sure each is fully incorporated. Mix in the vanilla.
On low speed, gradually blend in the dry ingredients until just combined. Cover and chill in the refrigerator for at least one hour.
Roll out half of the chilled dough onto a floured surface until an 1/8 inch thick. Keep the rest of the dough in the refrigerator until you're ready for it. Use cookie cutters to cut out shapes and transfer them onto a baking sheet lined with parchment paper or a silicone baking mat. Don't put more than 12 cookies on a pan.
Re-roll the scraps until you've used up the dough and then roll out the remaining chilled dough.
Chill each sheet of cookies for at least 30 minutes before baking. Preheat the oven to 375°F (190°C), and then bake the cookies (one pan at a time) for no more than 6-7 minutes. Don't worry if they still look a little soft when you take them out of the oven.
Leave the cookies on the baking sheet for 5 minutes before transferring them to a wire cooling rack.
Make the frosting while the cookies are cooling. Cream the butter and Crisco until smooth. Mix in half of the powdered sugar on low speed. Then add 2 tbsp of milk, 2 tbsp of heavy cream, the vanilla, 1/2 tsp of ginger and the remaining powdered sugar. Mix on low speed until just combined, and then beat on high speed until smooth and fluffy. Add another tsp of milk and heavy cream if the frosting is too thick. You can also add more ginger if desired.
Decorate the cookies and store in an airtight container in the freezer.