Joe Ortiz, a baker from Gayle's Bakery & Rosticceria in Capitola, Cali fornia, shows chef Julia Child how to make crusty sourdough bread loav es in several decorative shapes. First, he makes homemade yeast, pulli ng bacteria wild and yeast out of the air with a mixture of flour, mil k, water, and cumin. Adding more flour, he crafts a dough which he sha pes into a loaf garnished with a sheaf of wheat, and mini-loaves shape d like a star and a cluster of grapes.