CRUNCH LAYER:

1 c. graham cracker crumbs
1/2 c. firmly packed brown sugar
1/2 c. chopped walnuts
1/2 c. butter or melted butter

CAKE:

1 pkg. Pillsbury Plus yellow cake mix
1/2 c. water
1/2 c. orange juice
1/3 c. oil
3 eggs
2 tbsp. grated orange peel

Heat oven to 350 degrees; grease and flour 2 9 inch round cake pans. In small bowl, combine crunch layer ingredients until crumbly. Press half of mixture into each prepared pan. In large bowl, blend cake ingredients at low speed; pour batter evenly over crunch layer. Bake 30 to 35 minutes or until toothpick comes out clean. Cool 10 minutes; remove from pans; cool completely.

FROSTING:

1 can vanilla frosting
1 c. whipped topping, thawed
3 tbsp grated orange peel
1 tsp. grated lemon peel
11 oz. can mandarin oranges

In small bowl, beat frosting until fluffy. Add whipped topping and continue beating until light and fluffy. Fold in grated orange and lemon peel. Place 1 layer, crunch side up, on serving plate. Spread with 1/4 frosting; top with remaining layer, crunch side up. Spread remaining frosting on top and sides; arrange orange sections on top. Store in refrigerator.