Beat 1/2 cup softened butter and powdered sugar at medium speed with an electric mixer until creamy. Add egg yolk, beating just until blended. Add flour, and beat at low speed just until mixture is crumbly.
Press flour mixture on bottom and slightly up sides of a lightly greased 13- x 9-inch baking dish.
Bake at 350° for 20 to 25 minutes or until edges and surface are lightly browned. Remove from oven; sprinkle crust evenly with chopped pecans and cranberries, and let cool.
Bring brown sugar and next 4 ingredients to a boil, stirring constantly, in a saucepan over medium-high heat. Pour brown sugar mixture evenly over chopped pecans and cranberries in baking dish.
Bake at 350° for 15 minutes or until golden. Remove from oven, and let cool completely. Cut into 15 squares; cut squares in half diagonally to form triangles.