MAKE THE FILLING: In a medium mixing bowl, beat key lime (or lime) juice, 2 teaspoons of the lime zest, sweetened condensed milk and cream using an electric mixer or food processor. Beat until thickened, about 4-5 minutes in processor (longer with hand mixer). Mixture will be thick, but not stiff like whipped cream. Refrigerate mixture for an hour or two to firm up a bit more.

ASSEMBLE THE CUPS: Using small cups (1/4 -1/2 cup size) - even teacups are fine - layer a tablespoon filling, then one wafer - if cups are small, use a bit less than one wafer and break it up. Repeat 2 more times. Add an additional layer if you want to make larger portion sizes. Set the cups on a tray and cover with plastic wrap (or wrap them individually). Refrigerate for 4 hours or overnight.

DECORATE AND SERVE: Place a few chocolate wafers in a small sealed bag. Crush with a glass or rolling pin into fine crumbs. Sprinkle each cup with a pinch of cookie crumbs and lime zest. Serve and wait for the raves.