Preheat the oven to 350°F (175°C)
Line a baking sheet with parchment paper or a silicone baking mat
Prepare fortune slips by cutting paper into small strips and writing messages on them
Whisk together 2 large egg whites, 1/2 cup granulated sugar, 1/4 cup melted butter, 1 teaspoon vanilla extract, 1/2 cup all-purpose flour, and a pinch of salt
Mix until the batter is smooth
Drop 1 tablespoon of batter onto the baking sheet
Spread each portion into a thin 3-inch circle
Bake for 6 to 8 minutes until the edges are lightly golden
Remove one cookie at a time while still hot
Place a fortune slip in the center of the cookie
Fold the cookie in half
Bend the folded cookie over the rim of a cup or bowl to form the classic fortune shape
Place the shaped cookie in a muffin tin or egg carton to hold its shape while cooling
Repeat with the remaining batter
Let the cookies cool completely before serving