Hershey's Kiss Cookies

1 1/4 cups sifted all-purpose flour
3/4 teaspoon baking soda
1/4 teaspoon salt
1/2 cup butter
1/2 cup peanut butter
1/2 cup white sugar
1/2 cup packed brown sugar
1 egg
1/2 teaspoon vanilla extract
1/2 cup white sugar for decoration
unwrapped Hershey's kiss candies

1. Preheat the oven to 375 degrees F (190 degrees C). Sift together flour, baking soda, and salt; set aside.
2. In a medium bowl, cream together butter, peanut butter, 1/2 cup white sugar, and brown sugar until smooth. Beat in egg, then stir in vanilla. Gradually blend in the sifted ingredients. Shape dough into 1 inch balls. Roll in remaining sugar. Place 2 inches apart on ungreased cookie sheets.
   
3. Bake at for 10 to 12 minutes in the preheated oven.
   
4. Remove from oven and immediately press Kiss into center of cookie. Remove from pan to wire cooling rack.