Preheat the oven to 350 degrees. Prepare a 9×13 inch casserole dish with nonstick cooking spray.
Beat the cake mix with the water, applesauce, and eggs for 3 to 5 minutes or until well combined. Stir in the shredded carrots. Transfer to the prepared casserole dish.
Bake for 35 to 40 minutes or until a toothpick inserted in the middle returns clean. Place the casserole dish on a wire cooking rack and allow the cake to cool completely.
For the filling, beat the cream cheese with the powdered sugar until blended. Add the coconut, pecans, and pineapple, mixing until incorporated. Then, fold in the frozen whipped topping.
Cut the cake into cubes. Place half of the cake into the bottom of the trifle bowl.
Top with half of the cream cheese mixture. Repeat the layers of cream cheese mixture and cake.
Top the trifle with the additional frozen whipped topping and garnish as desired.