Line a large baking sheet with double thickness aluminum foil.

Sift flour, baking powder and salt into a medium bowl and set aside. Using an electric mixer beat butter and sugar in large mixing bowl until well blended. Beat in eggs 1 at a time, then add vanilla and orange liqueur, beating until well mixed. Beat in flour mixture until combined. Stir in cranberries, grated orange peel and pecans. 

Drop dough by heaping tablespoonful onto prepared sheet in two 10–11-inch-long strips, spacing strips 3 inches apart. Using a metal spatula, shape strips into 11-by 2½-inch logs. Refrigerate 30 minutes.

Preheat oven to 350°. Bake logs until tops are cracked and dry, and tester inserted into center comes out clean — about 25–30 minutes; cool 10 minutes.

Reduce oven temperature to 300°. Using foil as an aid, lift logs onto work surface. Line baking sheet with clean foil. Using a serrated knife gently cut warm logs crosswise on the diagonal into ¾-inch-thick slices. Arrange half of slices, cut side down on each prepared baking sheet. Bake biscotti until just dry to touch, about 8–10 minutes. Turn biscotti over. Bake until top is dry to touch, about 8 minutes. Cool on sheets.

Place white chocolate in small microwave-safe bowl and heat to melt, using 15-second intervals, stirring each interval until smooth. Dip side or end of biscotti to coat as desired.