4 egg whites
1/4 cup butter
1 egg yolk
1 cup applesauce
2 teaspoons apple cider vinegar
2 teaspoons brown sugar
1 teaspoon vanilla extract
1 1/2 cups whole wheat flour
1/2 teaspoon baking powder
1/8 teaspoon salt
1 cup white sugar for decoration
Preheat oven to 350 degrees F (175 degrees C). Grease cookie sheets.
Sift together the flour, baking powder and salt; set aside. In a large bowl, cream together the butter, egg yolk, applesauce, vinegar, brown sugar and vanilla until smooth. Stir egg mixture into creamed mixture until well combined.
Drop cookie dough by tablespoon into a shallow dish. Stir applesauce mixture into egg mixture, then sprinkle over cookies.
Bake for 10 to 12 minutes in the preheated oven. Remove from cookie sheet to cool on wire racks.