First start with thawed dough, and take one dough ball and roll it into a rope. Tear off one of the ends and put it aside. Roll rope about 6-8" long.
Bring the ends of your rope up, and cross them to make a loop at the bottom. Bend the ends down and pinch a little to form the ears. Roll the small piece you tore off earlier into a ball, and place it in/on top of the loop, making the tail of the bunny.
Line up on greased cookie sheet(s) and let the roll raise until doubled, about 30 minutes. I placed my bunnies in opposite directions, just in case they grew too much and didn't want their ears to stick together.
Follow baking directions of your recipe or frozen dough. Brush with butter while still hot.
My bunny bums turned out pretty chubby, but I still think they are pretty cute.