see yeast starter
From The Food Lover's Companion, Fourth edition by Sharon Tyler Herbst and Ron Herbst. Copyright © 2007, 2001, 1995, 1990 by Barron's Educational Series, Inc.
Our step-by-step guide makes tackling this days-long process way less intimidating.
Have a cup of water on hand.
Hint: It comes for free with your takeout.