Preparation
Put the orange juice into a small heat-proof bowl and sprinkle the gelatin over it.
Set aside for 5 minutes.
Peel mangoes, cut fruit from pits and puree in blender or food processor.
You should have 4 cups of puree.
Transfer puree to a large mixing bowl and stir in the sugar and evaporated milk.
Warm the juice and gelatin over a bowl of hot water until liquid and smooth.
Whisk the gelatin into the mango mixture.
Stir in the whipped topping.
Fill a 10 cup mold with cold water and pour all the water out.
Fill the mold with the mango mixture, cover with plastic wrap and refrigerate until set, at least 2 to 3 hours.
To serve, wrap a warm, damp towel around the mold.
Invert a serving plate over the mod and, holding plate and mold together, turn plate upright.
Lift the mold away carefully.
