Hmm...then why would you say "Two plain" and "Two are filled with or topped with chocolate"?!
I thin k I started with:
If a raspberry jam cookie is eaten just after cookie x, an apricot cookie has to be eaten before cookie x.
If I eat one with nuts, a cookie with jam must follow.
Oh, I see. Lack of specificity.
Well, we can say: two plain - one star shaped and one rectangle.
Two chocolate - one chocolate on it, one chocolate inside it. (kind of did cover that)
I always loved these kinds of questions on GRE tests and the like - although not so enjoyable under time pressure in a room with fluorescent lights...
Still, I may continue to create such brainteasers, at least for my blog.