Heat oven to 375° F.
Line 3 baking sheets with parchment paper. Set aside.
Remove one piece of dough from refrigerator.
Roll to 1/16" thick.
Use a 4" cutter to cut out circles.
Repeat with remaining dough.
Place ½ of the dough circles on prepared baking sheets.
Place remaining dough circles in refrigerator until ready to use.
Top each with ⅛ cup peach mixture.
Brush edges of dough with water or egg wash.
Top with remaining dough rounds.
Press all the way around the edges with fingers.
Use a fork to make sure the dough is sealed.
Cut slits in top of dough to allow steam to escape.
Bake for 15 minutes.
Brush tops with reserved peach liquid.
Sprinkle with sparkling sugar, if desired.
Bake an additional 20 minutes, until golden brown.