Easter bunny molds for resin, plaster and concrete. I recommend printing it in TPU, but I have also had success with PLA. It is best to brush the inside of the mold with household oil (such as that used for cooking) before casting. I've always got into the habit of pouring a small amount directly into the mold beforehand and then the concrete.

You can see both sides of the result in the pictures. For a little more color or variety, you can also chase the Bambu Lab poops through a blender and add them when pouring. This will add extra colors and allows recycling of the waste in a somewhat useful way!