Preheat the oven to 400 degrees.
In the mixer bowl, combine the egg whites & vanilla - beating with the paddle attachment until frothy.
Sift the flour, sugar & salt in a small bowl.
Add the flour mixture to the egg mixture & beat until it forms a thick batter.
On a heavily greased or silicone-lined cookie sheet - take a small amount of batter on a teaspoon & drizzle into a puddle. (I first started out with a Silpat - I found that the cookie sheet with heavy cooking spray worked much better)
Spread the puddle around until you have a thin circle approx 3 inches in diameter & uniform in thickness. Only do 2-3 at a time as once you pull them out from baking, you will have to work quickly.
Bake for 5 minutes or until edges are golden brown & center is still pale.
Remove & lift off the first one with a thin, offset spatula - flip upside down onto a cutting board and quickly place the fortune paper in the center.
Fold the cookie in half- pinching together & hold with one hand.
With the other hand, press into the center to form the bend & pull the ends down to form the cookie. This whole process of folding should take no more than 10 seconds before you move on to the next hot cookie waiting for you.
You can hang it over the edge of a glass until it's hardened or place in a muffin tin to help hold it's shape.
Repeat until all the batter is used up.
Store in an airtight container for up to 1 week.