Stir together the flour, sugar, and salt. Using a pastry cutter or a food processor, cut the shortening and butter into the flour until the mixture resembles coarse crumbs. It is only about 10 pulses with a food processor but a bit more work by hand. One trick to make the process a little easier is to freeze your butter beforehand, then grate it into the flour mixture before cutting it in with the pastry cutter if not using a food processor.

Sprinkle 2 tablespoons of the ice water over the mixture. Using a fork, gently stir the water in to the flour mixture, then repeat with the remaining water, adding only 2 tablespoons at a time, just until the dough starts to come together.

Divide the dough into two even pieces. Turn each piece of dough onto a sheet of plastic wrap and flatten each into a disc and wrap tightly in plastic wrap. Refrigerate for 1 hour, then allow the chilled dough to sit on the counter to soften slightly for 10 minutes before rolling out.

Heat oven to 400 degrees. Roll out the bottom crust and line a pie plate with it.

To easily peel the peaches, gently lower them into a large pot of boiling water for 40-60 seconds, then remove to an ice water bath with a slotted spoon to shock them. After just a few seconds, the skin should slip off easily by just rubbing the peaches with your fingers. Remove pits and slice the peaches.

In a large bowl, combine the fresh, sliced peaches with the sugar, cornstarch, flour, cinnamon, allspice, salt, vanilla and lemon juice and toss to evenly coat the peaches.

Fill the bottom pie shell with the peach mixture, including the juices that will be released from the peaches. Dot with butter, then roll out the top pie crust and gently transfer it over the peach pie filling. Crimp the edges and cut a few slits in the top of the crust, then brush with the beaten egg and sprinkle with coarse sanding sugar.

Place pie on a baking sheet and bake in oven for 45-50 minutes, until the filling is bubbling and the crust is nicely browned. You may need to cover the edges with foil during the last 15-20 minutes of baking to prevent them from getting too brown.

Remove the pie from the oven and cool for at least 3 hours before cutting into it. Serve with vanilla ice cream.