Prepare chocolate pudding per pkg. directions.
Meanwhile, in 9- by 13-in. baking dish, arrange 1 layer of graham crackers in bottom, breaking as needed to cover entire dish (6 to 7 crackers total). Spread chocolate pudding evenly over graham crackers.
Prepare vanilla pudding per pkg. directions.
Meanwhile, arrange second layer of graham crackers over chocolate pudding, breaking as necessary (7 to 8 crackers total). Spread vanilla pudding evenly over graham crackers. Cover and refrigerate overnight, up to 2 days.
When ready to serve, using electric mixer, beat heavy cream, confectioners’ sugar and salt until soft peaks form, 1 to 1 ½ min. Spread evenly over vanilla pudding. Using fine-mesh sieve, sift cocoa powder and cinnamon over whipped cream.
