Place the flour, salt, and sugar in a food processor. Pulse a few times to mix. Add the COLD butter and shortening cubes and pulse until the mixture resembles peas.
Add the amaretto and 1 tablespoon of cold milk. Pulse again until the dough comes together. Add another 1-2 tablespoons of milk if needed. Dump the dough out onto a sheet of plastic wrap. Separate into two equal pieces and flatten into two disks.
Wrap each disk in plastic and refrigerate for at least 30 minutes, or until ready to use.
If baking with pie weights:
Preheat the oven to 375 degrees F. Roll the dough into a large even circle, 12 to 13 inches across. Fit the pie crust into a pie pan. Crimp the edges. Then place a piece of parchment paper in the crust. Fill with pie weights and bake for 18-20 minutes.