- Line the bottom and the inside walls of a 20-cm (8-inch) springform pan with parchment paper.
- Place the ice cream sandwiches upright, sticking them side-by-side on the inner walls of the pan. Place the remaining sandwiches at the bottom of the pan, cutting them as needed. Set aside in the freezer.
- In bowl, whip the cream with the sugar and vanilla until stiff peaks form.
- In another bowl, soften the ice cream with a wooden spoon. Fold in the whipping cream, stirring gently with a spatula until the mixture is just marbled. Pour into the pan. Freeze for 4 hours or overnight. Just before serving, unmould the charlotte and garnish with the cookies.
For a Neapolitan-style charlotte, substitute 500 ml (2 cups) of chocolate ice cream with strawberry ice cream.