Fractal cookies, from Evil Mad Scientist Laboratories
Take nine "square cylinders" (i. e. rectangular solids which are much longer in one direction than the other two) of dough, one of which has chocolate in it.
Arrange the nine sticks in a three-by-three grid with the chocolate one in the center; squish them together so that they are one big piece of dough.
Stretch the whole thing to eight times its current length; cut into eight pieces of equal length (the length of the original piece), each of which will have a chocolate center. (This can be done by stretching to twice the length, cutting in half, and repeating twice more.)
Add a piece of chocolate dough of the same size; again arrange in a three-by-three grid with the chocolate one in the center, stretch, and cut. Then do it again. Then cut the whole thing into slices and cook.
Of course, you get the Sierpinski carpet in cookie form.
However, at the level of iteration given here, (8/9)3, or about seventy percent, of the cookie will consist of non-chocolate dough! This is sad. I recommend interchanging the chocolate and non-chocolate doughs.
See also the Sierpinski gaskets made from polymer clay, which are made by a similar process. These are inferior, because they cannot be eaten.