Place 6 cookies on a serving plate in a circle and add a seventh to the center. Keep in mind that it is nearly impossible to transfer the cake to a different plate, so pick the plate you'd like the cake to ultimately be served on.
Using a small offset spatula or butter knife, dab a bit of the whipped cream mixture beneath each cookie to anchor it to the plate.
Place a scant 1/2 cup of cream on top of the cookies and spread the cream not quite to the edges of the cookies.
Place another layer of cookies atop the whipped cream, staggering them (i.e. placing each cookie on this layer atop the space between two cookies on the prior layer). I like to use a tablespoon cookie scoop, or measuring spoon, and place a generous tablespoon of cream on top of the center cookie and on top of the space between each of the remaining cookies (rather than dolloping on a 1/2 cup portion).
Apply another 1/2 cup of cream, and another seven staggered cookies, and continue doing so until you have a ten-layer cake.
Place a final layer of whipped cream on top of the cake.
Lightly cover with plastic wrap and let set-up in the refrigerator for at least 6 to 8 hours.
Decorate with sanding sugar or sprinkles.
Slice as you would a layer cake and serve.
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Notes
If you choose not to use a chocolate wafer, select a cookie that is thin and very crispy. Graham crackers and ladyfingers work well if you choose to use pudding instead of whipped cream.You don't need to make this cake on a plate. Icebox cakes can be assembled in any vessel or in any shape that you choose, provided you remember this: cakes made with pudding or runny add-ins such as caramel or ganache do best in vessels with sides to eliminate oozing and spillage.Other decorating options include crushed candy, chocolate curls, or sprinkles.