In a medium mixing bowl using a hand mixer whip together the sweetened condensed milk, cream cheese and pudding mix. Beat for 2 minutes until the cream cheese has completely incorporated. Whip in ½ of the whipped topping.
Spread the filling into the graham cracker crust. Top with the remaining whipped topping. Sprinkle with ground cinnamon.
Chill for at least 4 hours or overnight before cutting.