Preheat Wolf oven in CONVECTION at 325°F. In large mixing bowl, combine butter, sugar and egg yolk; beat until light and fluffy. Add flour, nuts and lemon peel; mix thoroughly. Shape dough into ball; divide into 8 pieces. On ungreased baking sheets, flatten each piece to 5-inch round, press edges to smooth. Combine sugar and ground ginger. Sprinkle tops with ginger sugar.
Bake for 15 to 25 minutes or until edges are light golden brown. Cool 5 minutes. Cut each round into 8 wedges; pierce surface with fork. Cool on baking sheet for 15 minutes or until completely cooled.
To Make Ahead:
Dough can be made ahead. Flatten between plastic wrap and place in Subzero refrigerator or freezer. When baking, allow to warm to room temperature. Bake in preheated Wolf oven in CONVECTION at 325°F for 20 to 25 minutes. Allow to cool on baking sheet for 5 minutes. Cut and serve.