40(2-inch) gingersnap cookies, finely ground
1/2 cup (1 stick) unsalted butter, melted and cooled
Using a food processor, grind cookies into a fine crumb. A plastic bag and mallet would work here, too.
Stir together gingersnap crumbs and butter in a bowl until crumbs are evenly moistened.
Spray cupcake tins with a light cooking spray.
Using a portion scoop (1/4 cup size), place the crust into each cupcake tin. Press and even out bottoms.
Bake both cupcake tins in middle of oven until edge is golden brown, about 5 minutes (watch carefully toward end of baking; crust burns easily).
Cool in pan on racks.