Bake cake mix according to package directions. You can either use a 13x9 inch dish or the two 8–9 inch round options.
Let the cake cool completely and cut into 1 inch pieces.
In a large bowl, whisk together the instant vanilla pudding and the milk. Let sit for 10 minutes to firm up a bit.
Place half of the cake cubes in a punch bowl or large trifle dish. Top with half of the vanilla pudding mixture.
Top with half of the cherry pie filling, then half of the pineapple tidbits and half of the mandarin oranges.
Repeat with the remaining cake, vanilla pudding, cherry pie filling, pineapple, and mandarin oranges.
Top with the whipped topping, then sprinkle the pecans on top.
Refrigerate for 1 hours before serving.
Notes
You can prepare this cake up to 8 hours in advance of serving it. Cover with plastic wrap and keep in the refrigerator. You can substitute sliced bananas or sliced fresh strawberries for the mandarin oranges.