Preheat oven to 350°. Spray 2 8-inch cake pans with non-stock cooking spray. Line bottoms with wax or parchment paper and spray paper. Dust with flour; set aside.
Cake: Beat devil’s food cake mix, cocoa, mayonnaise, eggs and water until blended. Beat two more minutes on high. Divide cake batter evenly into two pans.
Bake about 35 minutes or until tests done. Cool for 20 minutes in pans and then remove onto racks. Peel off paper to cool completely.
Filling: Whisk frosting, sour cream and vanilla. Transfer 1 1/2 cups into a medium bowl and stir in almonds and coconut; set aside.
Frost the Cake: Using a serrated knife, split each cake in half. Place one layer, split side down, on serving platter. Place 1/3 of filling on top of layer and spread evenly. Repeat with following layers until final cake layer. Spread frosting over the top and sides of cake. Can store up to 4 days.