Orange Crunch Cake

Step 1
Preheat the oven to 350 degrees F (175 degrees C). Grease and flour two 9-inch pans. Combine graham cracker crumbs, brown sugar, walnuts, and butter. Divide mixture evenly between the prepared pans. Set aside.

Step 2
In a medium bowl, mix together cake mix, water, orange juice, and oil until blended. Beat in eggs, one at a time, then stir in orange zest. Pour mixture evenly over crunch layer in the pans.

Step 3
Bake in the preheated oven for 30 minutes, or until a toothpick inserted into the center of each cake comes out clean. Allow to cool in pans for 10 minutes; invert onto a wire rack and cool completely before frosting. Frost (crunch-side up) between layers, on top and sides. Arrange mandarin orange segments on top; refrigerate.

Step 4
To make frosting: In a medium bowl, beat vanilla frosting until light and fluffy; mix in whipped topping. Stir in orange and lemon zest. Use frosting on completely cooled cake layers.