Lime Truffle Pie

Directions

1. For the crust, pulse the pistachios in a food processor until they are fine.  Add the flour, salt and sugar and pulse to blend.  With the processor running, drizzle in the egg yolk until blended.  Move mixture to a medium bowl.
2. Using a pastry blender or forks, cut in the butter until the dough looks like coarse cornmeal.  Cut in the shortening until it’s distributed and the lumps are the size of peas.  Add ice water one tablespoon at a time and, using forks, fluff to moisten the dough.  Add just enough ice water, a little at a time, for the dough to hold together when you gently press a spoonful together in your hand.  Transfer to plastic wrap, flatten into a disc, and chill for 30 minutes.
3. Move an oven rack to the center position and preheat to 450°. 
4. Roll out the dough and transfer it to a 9” glass pie plate.  Trim (there will be extra dough) and make a scalloped edge.  Chill again for at least 10 minutes.
5. Use a pie chain or pie weights in the bottom of the pie plate and bake for 12-16 minutes or until the crust is evenly golden.  Use a crust protector to keep the edge from getting too dark, if need be.  Watch during baking to see if the crust is poofing up.  If so, quickly reach in with a fork and lightly prick any bubbles so that the crust is evenly thick all over.  When done, let the crust cool to room temperature.
6. Make the chocolate layer by beating the butter with an electric mixer until light.  Alternating with the milk, beat in the dry ingredients until well blended.  Use a few extra drops of milk if needed for a frosting-like consistency.  Stir in vanilla.
7. For the filling, whisk the eggs and yolks together in a small bowl.  Melt the butter in a heavy medium saucepan over medium heat.  Whisk in most of the sugar (having set aside 2 T. of it) and the lime juice and zest.  Slowly whisk a little of the hot mixture (about ¼ cup) into the eggs, then whisk the eggs into the pot.  Cook over medium heat until the mixture thickens, whisking constantly, which takes several minutes (up to 10).  Reduce heat to low and whisk 2 minutes longer.  Stir in 1 tiny drop of green food color if desired (but only one!).  Transfer to a bowl, cover with plastic wrap on the surface, and chill.
8. Line a cookie sheet with parchment paper or foil.  Stir 2 T. sugar and 4 t. water in a heavy small saucepan over low heat until the sugar dissolves.  Increase heat and boil without stirring until pale golden, about 6 minutes.  Add the ½ c. pistachios and stir to coat.  Remove from heat.  Spread nuts in a single layer on the prepared sheet.  Cool completely, then coarsely chop pistachios and store at room temperature in airtight container until just before serving.
9. When both the pie shell and the cooked filling are cool, spread the chocolate layer on the inside of the pie shell and about ½ of the way up the inside of the crust.  (You may only want to use half of the chocolate, depending on your taste.)  Smooth to even thickness.  Pour the cool filling over the chocolate and lightly swirl the top.  Chill completely, at least 2 hours.
10. Before serving, top with candied pistachios and a little grated chocolate (or make chocolate swirls using a cake decorating tip and any extra chocolate filling).