Preheat oven to 350 degrees. In the bowl of an electric mixer, beat together cake mix, eggs, and butter until smooth. The dough will be stiff and sticky.
Drop by tablespoons onto a Silpat of parchment lined baking sheet. I did 9 cookie per sheet.
Bake for 8 minutes, then let them cool on the pan for 3-4 minutes before transferring them to a cooling rack.
To make the cookies easier to work with when you are making the ice cream sandwiches, try freezing them for about an hour so that they are firmer. I made room in my freezer for the whole cooling rack so that they could be a single layer and not stick together.
Once they are frozen, place a scoop of ice cream on one cookie and top with another. Press them together gently so the ice cream scoop flattens. Use a spoon to scrape off excess ice cream. Freeze immediately.