Chill the mixing bowl and whisk for 3 to 4 hours before making this dessert.
Peel the mangoes, slice each side then slice the pieces into strips. Set aside.
In a chilled bowl, mix together the heavy whipping cream and condensed milk. (Add tsp of vanilla extract if available). Beat in medium speed until the size doubles or stiff peaks form.
Assemble the layers in a clear dish pan. Graham crackers, whipped cream, and mango slices. Repeat until you've used up all the 3 components. Cover the pan with saran wrap. Chill in the fridge for 8 hours or overnight.
