Preheat oven to 350°F for 5 Minutes. Butter three 9-inch-diameter cake pans with 1 1/2-inch-high sides. Line bottom of pans with parchment paper. Combine 1/3 cup flour and next 3 ingredients in processor. Process until nuts are finely chopped. Whisk remaining 2 cups flour, cinnamon, baking powder, salt, and baking soda in medium bowl to blend.

Divide batter among pans. Bake until tester inserted into center of cakes comes out clean, about 30 Minutes. Cool in pans on racks 1 hour. Run knife around edge of pans to loosen cakes. Turn cakes out onto racks; cool completely.

Place 1 cake layer, flat side up, on platter. Spread 3/4 cup frosting over top of cake. Top with second cake layer, flat side up. Spread 3/4 cup frosting over. Top with third cake layer, rounded side up, pressing slightly to adhere. Spread thin layer of frosting over top and sides of cake. Chill cake and remaining frosting 30 minutes. Spread remaining frosting over top and sides of cake. Arrange whole nuts and ginger around top edge of cake. Chill 40 Minutes. (Can be made 1 day ahead. Cover with cake dome and chill. Let stand at room temperature 1 hour before serving.)