People who spin their own yarn apparently use a tool called an orifice hook. Yes, they do. It's true. I know this because someone who advertises on Ravelry mentioned them in her ad.
Disappointment: her Etsy shop is out of them, so there are no pictures there to reign in the imagination.
Tomorrow, if I get a chance, I will post the recipes for Eric's birthday cake and for the picnic fare that will proceed it.