Preheat oven to 375°F.
Roll pie dough onto a lightly floured surface.
Cut chocolate bar into pieces of 3 segments, vertically aligned.
Cut dough into rectangles big enough to fit 3 chocolate bar segments with extra room on all sides for crimping. (It’s recommended to keep the 3 segments together, as it’ll help the lollipop stick stabilize better later.)
Knead and roll dough scraps to cut out more rectangles.
Place 3 chocolate bar segments and about 7-10 mini marshmallows on a rectangle of dough.
Add a lollipop stick, then top with another rectangle of dough.
Roll edges and crimp with a fork.
Place pie pops on a baking sheet and brush with beaten egg whites.
Sprinkle with sugar.
Bake at 375°F for 12-15 minutes.
Allow pie pops to cool for a couple of minutes before pressing the lollipop stick down into the chocolate bar to stabilize it.