First, don't assemble the empanadas until you're ready to bake them or the liquid from the filling will make the uncooked dough soggy. Second, make sure to let the baked empanadas cool COMPLETELY on a cooling rack before storing them. If you put them into a container before they're cooled to room temperature, condensation will form and cause the dough to get soggy. Finally, make sure you use a toaster oven, air fryer, or regular oven to reheat your empanadas. While you can technically heat them in the microwave, they won't retain their crispiness if you do.