Sweet Sandwich Cookies

Directions

1. In a large bowl, cream butter and brown sugar until light and fluffy. Beat in egg yolk. Combine flour and salt; gradually add to creamed mixture and mix well. Cover and refrigerate for 20 minutes.
2. Shape into 1-in. balls. Place 1-1/2 in. apart on ungreased baking sheets. Flatten with a fork, forming a crisscross pattern.
3. Bake at 325° for 8-10 minutes or until golden brown. Remove to wire racks to cool.
4. For filling, heat butter in a saucepan over medium heat until golden brown. Remove from the heat; stir in confectioners' sugar, vanilla and enough milk to achieve spreading consistency. Spread on the bottoms of half of the cookies; top with remaining cookies.