Ingredients

• 1 can sweetened condensed milk
• 1 cup soy, almond, rice or dairy milk
• 1 cup whiskey
• 1 tbsp chocolate syrup
• 1 tsp instant coffee, Roma or chickory
• 1 tsp coconut extract
• 4 egg whites

Instructions

Mix all above ingredients except egg whites.  Set aside. 
 
Beat egg whites to a soft peak, then fold into above mixture.

Chill. Shake. Serve.

Variations 

For less sweet -- double the batch but use one can sweetened condensed milk and 1 can evaporated milk.

Make a double batch by using 1 cup of half & half or non-dairy creamer instead of milk and 1 cup very strong coffee instead of instant.
 
There were other variations, but they didn't get written down, probably due to the quality control procedures performed during the making of such batches (ie monitoring whiskey quality).