Bake cake in a 13 x 9 inch baking pan according to the package’s directions. Cut into cubes.
Pour pudding into a bowl and add milk and Kahlua; mix well.
Leave Heath bars in wrappers and pound with hammer to crush.
In a very large pretty Trifle dish or glass bowl, layer in this order:
½ cake cubes
½ pudding mixture
½ whipped, whipping cream
½ heath bars
Repeat layer. Cover with plastic wrap and refrigerate overnight.
**Heath bar pieces may be found in the baking section of the grocery store. If you use the pieces instead of bars, you just need one bag.