Sift the flour and salt into a large bowl. Cut in the shortening and the butter using a pastry cutter until the mixture resembles coarse crumbs.
Mix the water and vinegar together in a cup. Add the water mixture to the crumbs. Mix together just until the dough is combined and handles well.
Sprinkle flour on the counter before rolling out the dough. Split the dough into two balls.
Roll out one dough ball on a floured surface using a rolling pin. Roll the dough about ½ an inch larger than your pie pan.
Lay the crust in the bottom of a 9-inch pie dish and press down lightly on the bottom and up the sides of the pan, allowing the edges to hang over.
Roll out the second dough ball. If desired use a small heart cookie cutter to make cut out hearts as you would like. Then set both aside while you make the filling.
Make the pie:
Preheat the oven to 350ºF.
In a bowl, gently mix the raspberries, arrowroot starch, tapioca, and sugar.
Pour the raspberry filling into the bottom pie crust.
Dot the top with 1 tablespoon of butter that you've cut into small chunks.
Lay the rolled out dough over top the filling. Fold the top edges of the dough under the bottom dough layer and use your fingers to crimp or pinch/seal it together.
Sprinkle granulated sugar on top of the pie crust. If you did not make cutouts in the dough, use a sharp knife to cut 2-3 slits in the top of the pie so it can vent.
Bake for 55-60 minutes, or until the crust is lightly browned.
Allow the pie to cool completely before slicing so the filling has time to firm up.
Notes
For a sweeter pie, increase the sugar by 1/4 cup. Raspberry filling recipe is from Taste of Home.Fruit pies are beautiful with a lattice crust.If you'd like a shiny, browned crust, whisk together 1 egg and 1 tablespoon of water, then brush the top of the pie with a pastry brush before baking.Refer to the article above for more tips and tricks.The calories shown are based on the pie being cut into 8 pieces, with 1 serving being 1 slice of pie. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information. The information in the nutrition box are calculated through a program and there is room for error. If you need an accurate count, I recommend running the ingredients through your favorite nutrition calculator.**