Jello and Evaporated Milk Dessert
Kraft has a recipe that resembles what you describe, in which you could substitute whipped evaporated:

3/4 cup boiling water
1 package (3 oz.) JELL-O
ice cubes
1/2 cup cold water
1/2 cup Cool Whip

Add boiling water to gelatin mix in a medium bowl; stir 2 minutes, until completely dissolved. Pour into blender. Add enough ice to cold water to measure 1-1/4 cups; add to blender. Blend 30 seconds or until smooth. Add the whipped evaporated milk; blend well. Pour into 4 dessert dishes. Refrigerate until firm.

To whip evaporated milk, an easy method is to pour the contents into a metal or glass mixing bowl, and place it (and, separately, the beaters) in the freezer for 30-45 minutes, until ice crystals begin to form. Remove and beat at high speed until thick, 3-4 minutes. 

Alternatively, food author Liz Berg has devised a method that emulates the discontinued Jello 1-2-3 product that separated into layers:

6 ounce box of Jello
1/4 cup heavy cream, whipped [substitute whipped evaporated] 

Divide dry Jello into two medium sized bowls. Add one cup boiling water to first bowl and stir till all sugar is dissolved. Add one cup of cold water and mix till combined. Pour mixture into clear glasses (6-8 depending on size) filling to halfway point. Chill till slightly jelled, about 30 minutes.

When the bottom layer is slightly jelled, whip the cream and repeat the process with the second bowl of dry gelatin, decreasing the cold water to ¾ cup. Whisk in the whipped cream and pour the Jello mixture on top of the first layer. Chill till set, about 4 hours.