Preheat oven to 350°F.

In a medium mixing bowl, combine brownie mix, water, vegetable oil, egg, and all purpose flour, stirring just until blended.

Drop by rounded tablespoonfuls onto a foil lined baking sheet.

Bake 12 to 15 minutes, or until set when lightly pressed with your finger.

Remove from pan and cool on a wire rack.

For filling, combine egg whites, cream, vanilla, and 2 cups confectioners' sugar, beating until smooth.

Add shortening and remaining sugar, beating until fluffy.

Spread a generous amount of filling on the bottom of 1 cookie and place another cookie on top of the filling.

Store in the refrigerator in an airtight container.

*This recipe makes about 10 cookies.*