In a large saucepan, add the lemon juice, vanilla, cornstarch, sugars, cinnamon, and water, and then whisk. Bring to a boil. Over medium heat, continue to whisk the ingredients for 2-3 minutes as the filling thickens. Prep the peaches. Wash and slice the peaches into 1/4-inch thick slices.
You can purchase canned sugar-free peaches at most supermarkets. If you don’t really care if the pie is sugar-free, then use peaches canned in regular syrup. They’ll be fine. Once you have your peaches, you’ll need to pour a quart of them into a pot.
Spread the peaches out in a thin layer. Sprinkle with blueberries. Melt the remaining butter, swerve and cinnamon together and stir. Drizzle the butter mixture over the top of the fruit. Bake the pie for 35 – 40 minutes, or until the peaches are soft, and the juices are bubbling up through the fruit.
Arrange the pies on a greased cookie sheet, cut a small slit in the top crust to create a vent, and bake them for 15 - 20 minutes or until nicely browned. You can make these Amish fry pies with any kind of pie filling that you desire. And if you buy the fruit filling, you will need about 3 cans of pie filling to make this whole batch of fry pies.