Preheat oven to 350. Prepare 9x13 baking dish by spraying with non-stick baking spray.
Add dry cake mix to medium-sized mixing bowl. Add water, applesauce, and eggs. Beat for 2 minutes then fold in carrots. Add batter to prepared pan and bake for 30-35 minutes or until toothpick inserted comes out clean.
Cool completely. Once cool, cut cake (while in the pan) into small squares.
While cake is baking, add pineapple to a saucepan over medium-high heat. Add cornstarch and brown sugar then mix well. Bring to a boil, stirring often. Once thickened (about 1-2 minutes), remove from heat and cool completely.
In a small bowl, beat heavy whipping cream until stiff peaks form. Set aside.
In a larger bowl, beat cream cheese, sugar, salt, and vanilla until smooth. Fold whipped cream into the cream cheese mixture. Set in fridge until ready to use.
In a trifle bowl (or large glass bowl), layer 1/3 of the cake cubes, 1/3 of the pineapple filling, then 1/3 of the cream. Repeat two more times ending in cream. Top with crushed cookies.
Refrigerate at least 3 hours before serving.