1 package active dry yeast
2 1/2 cups warm water (110 degrees F)
2 cups all-purpose flour, unsifted
1 tablespoon granulated sugar

In a 6-cup glass or ceramic container soften yeast in 1/2 cup warm water. Stir in remaining 2 cups water, flour and sugar. Beat mixture until smooth. Cover loosely with cheesecloth, folded into several thicknesses and let stand at room temperature until bubbly. This may take 5 to 10 days, depending upon the temperature of the room the warmer the room, the shorter the time for fermentation. During this time, stir 2 or 3 times a day. The starter will develop a strong "sour" odor as it ferments. When fermentation has occurred, refrigerate starter until needed.

To renew starter after using portions
3/4 cups all-purpose flour
3/4 cup water
1 teaspoon granulated sugar

Add the above to the remainder of the old starter for each cup of starter used. Stir well. Let stand at room temperature until bubbly, at least 1 day. Cover loosely and refrigerate. If not used within 10 days, stir in 1 teaspoon sugar. Repeat the addition of 1 teaspoon sugar every 10 days.