In a bowl, gently toss the sliced peaches with sugar, flour, vanilla extract, Campari/Aperol, and a pinch of salt. Allow the mixture to sit for about 15 minutes.
Preheat your oven to 425.
Meanwhile, roll out the pie crusts and cut into 3-4 circles that are about 5-6" in diameter, re-rolling dough as needed. Place the prepared pie crust circles on a baking sheet lined with parchment paper.
Spoon a small amount of the peach filling onto the center of each crust, leaving about 1-1.5 inches of crust around the edges, then fold the edges of the pie crust over the filling.
Brush the edges of the pie crust with beaten egg, then sprinkle a little turbinado sugar over the exposed peach filling and the edges of the crust.
Bake the mini peach galettes in the preheated oven for about 20-25 minutes, or until the crust is golden brown and the peach filling is bubbling.
