1 qt. lukewarm water
1 pkg. dry yeast
2 tsp. sugar
4 c. all-purpose flour

Put water in crock, add yeast and sugar to soften. Stir in flour. Cover with a clean cloth. Let rise until mixture is light and slightly aged, about 2 days. Mixture will thin as it stands; add flour as needed. As you use sourdough from the crock, replace it with equal amounts of flour and water.