Preheat oven to 425 degrees F (220 degrees C). Whisk together the powdered milk, cornstarch, stevia powder, cinnamon, and salt in a small bowl; set aside.
Place apricots, raisins, and water in a small saucepan over medium heat, and bring to a boil. Boil for 5 minutes, stirring occasionally. Stir in the powdered milk mixture, and cook, stirring constantly until the mixture thickens, about 3 minutes. Remove from heat; stir in white vinegar and butter. Allow to cool for 15 minutes.
Turn the filling into a pastry lined pie pan. Cover with top crust. Seal edges, and cut slits in the top crust.
Bake in the preheated oven until crust is golden brown, 30 to 35 minutes. Remove from oven and allow to cool before slicing.
You can also use brown sugar in this recipe. Substitute 1/2 cup brown sugar for the 1/2 teaspoon stevia powder.
For the crust, I use the Basic Flaky Pie Crust off this site. Instead of the shortening, I use butter, and I double the recipe to make a double crust pie.