Thaw puff pastry according to package instructions
Preheat oven to 350 degrees F
Line baking sheet with parchment paper or lightly grease
Roll each sheet puff pastry out to approximately 11x13 inch rectangle
Spread Nutella over one sheet of pastry
Add other sheet of puff pastry to the top
Using cookie cutters, cut out shapes
Place shapes onto parchment lined baking sheet
Whisk egg and brush the tops of cutouts
Bake for 14-18 minutes or until golden brown IMPORTANT NOTE: Check cutouts during baking to make sure they stay sandwiched together. Occasionally the puffing causes them to separate. Use tongs to place them back together and smoosh together a little.
Allow cutouts to cool
Decorate with icing of choice
Dust with powdered sugar