The Very Hungry Caterpillar by Eric Carle is a classic. Beautifully illustrated with collages, it's short enough to keep a preschooler's attention. It is about a caterpillar who turns into a butterfly and eats a lot in between.
This is my son's favorite page. As you can see, he has to actually lay the food on top of the book to be sure it matches closely enough. Good thing it's a board book. We did the food first and lost a little steam making that sad little caterpillar...
I often suggest making the butterfly on the last page instead, but my son always insists on making the food.
Have you ever recreated something from a book using play dough?