In a large bowl, cream butter, cream cheese and sugar until light and fluffy. Beat in egg and extracts. In another bowl, whisk flour and baking powder; gradually beat into creamed mixture. Stir in chocolate chips., Divide dough into 10 portions. Shape each into a disk; wrap in plastic. Refrigerate 2 hours or until easy to roll., Preheat oven to 375°. On a lightly floured surface, roll each portion into a 24-in. rope; cut into 2-in. lengths. Place 1 in. apart on ungreased baking sheets; curve to form crescents. Bake 6-8 minutes or until edges are light brown. Remove to wire racks to cool completely., In a small bowl, melt chocolate chips and shortening; stir until smooth. Dip each cookie halfway into chocolate mixture; allow excess to drip off. Sprinkle with walnuts. Place on waxed paper; let stand until set., To Make Ahead: Dough can be made 2 days in advance. Wrap in plastic and place in a resealable bag. Store in the refrigerator., Freeze option: Freeze cookies, layered between waxed paper, in freezer containers. To use, thaw before serving.