Heat oven to 350° F. Line medium muffin cups with paper baking cups.
In medium bowl, combine flour, baking powder, baking soda and salt; set aside
In a large bowl beat butter, granulated sugar, brown sugar, egg and vanilla until light and fluffy.
Gradually mix flour mixture into butter mixture. Add milk and stir until just blended.
Stir in cranberries, walnuts and 2/3 cup chocolate chips. Fill muffin cups about almost full with batter.
Bake 18 to 20 minutes or until wooden pick inserted in center comes out clean. Cool 5 minutes; remove from pans to wire rack. Cool completely.
Meanwhile prepare glaze by placing remaining 1 cup chocolate chips and vegetable shortening into a small microwave-safe bowl and microwave at HIGH for 30 seconds; stir. If necessary, microwave at HIGH an additional 15 seconds at a time until chips are melted when stirred. Drizzle evenly over tops of cupcakes and refrigerate to set glaze.
Servings: 2 dozen