Cream the butter, shortening and sugar. Then add the eggs and vanilla. Once this has been incorporated, add dry ingredients and combine them well. After your dough pulls away from the bowl, it's ready to divide into containers and dyed to the colors you wish.
Try to use the gel colors so you don't add too much moisture to the dough. (Use a toothpick to get any tiny amounts and add until you get your desired hue.) Once your rainbow-colored doughs are complete you will need to put each one, separately, into ziplock bags and let chill for at least one hour.
When it's time to roll out your poops, divide the dough into equal portions of color for each cookie. On a floured surface, roll your portions/colors into snakes and layer the colors on top of each other. Press them to compact into a bigger snake, then twist the dough opposite ways (like a towel that you are going to whip someone with), then coil into your poop shape.
Try to keep the sizes consistent so that your cookies won't be too thick to bake through. You will know when they are done by seeing a light browning on the bottom of the cookies and the tops will be dry.
To decorate, you can choose to use sprinkles of your choice and if you wish -- you can use some edible glitters or sugar pearls! To make it all stick, you can use Wilton Sparkle Gel from your local cake supply store.
Preheat oven to 400, bake for 12-14 minutes.
Here is another version of unicorn poop cookies, her recipe is slightly varied but if you prefer video instructions ( and a cute one at that) this might be the one to go with. Enjoy!