Sourdough Starter - cooking recipe

Ingredients

1 cake yeast or envelope dry yeast
4 c. warm water
2 Tbsp. sugar
4 c. flour
1 raw potato, quartered

Preparation

Dissolve yeast in warm water, then mix all ingredients in a 1-gallon crock or other nonmetallic container.
Cover with a close fitting lid and let starter rise until light and bubbly on top (12 hours in warm weather, longer in cool weather). Never let starter get cold.
After each time you use starter, add 1 cup warm water, 2 teaspoons sugar and enough flour to return the starter to its original consistency.
Add more potato as food for the yeast (when original potato is used up), but don't add yeast.