Heat oven to 350°F. Spray cookie sheet with cooking spray. In medium bowl, mix pumpkin, brown sugar, cinnamon, ginger, nutmeg and egg yolk. Stir in 1/2 cup pecans.
If using crescent rolls: Unroll dough onto cookie sheet; firmly press edges and perforations to seal. Press to form 13x7-inch rectangle. If using dough sheet: Unroll dough onto cookie sheet. Press to form 13x7-inch rectangle. Spread filling in 3 1/2-inch-wide strip lengthwise down center of dough rectangle to within 1 inch of ends.
With scissors or sharp knife, make cuts 1 inch apart on long sides of dough rectangle just to edge of filling. Fold strips at an angle across filling, overlapping ends and alternating from side to side. Beat egg white in small bowl until foamy; brush over dough.
Bake 20 to 30 minutes or until deep golden brown. Immediately remove from cookie sheet; place on serving platter.
In small bowl, mix powdered sugar and enough milk for desired drizzling consistency. Drizzle over warm coffee cake. Sprinkle with 1 tablespoon pecans.