Guests will love this simple shortbread cookie sandwich using your leftover Trefoil cookies. Spread a dollop of Nutella or chocolate-hazelnut spread and then add a toasted marshmallow for a delicious cookie sandwich treat.
On a parchment lined baking sheet arrange the 24 Trefoil cookies in pairs. On a separate sheet pan, lined with foil, arrange the marshmallows in one even layer. Place the marshmallows under the broiler in your oven for about 30 seconds to 1 minute or until browned. Place two mini marshmallows on 12 of the cookies. Spread a spoonful of Nutella onto the remaining 12 cookies. Place together to form marshmallow and Nutella sandwiches. Then, melt the chocolate over a double boiler. Dip the cookie sandwiches into the chocolate and place on a sheet pan lined with wax paper. Place the cookie sandwiches in the fridge to set for about 5 minutes. Remove, and enjoy.