Betty Crocker has a good sourdough bread recipes for bread machines and A Thrifty Mom publishes a good recipe that doesn't require a sourdough starter. Sour cream, butter and white vinegar take the place of starter in A Thrifty Mom's recipe. Both recipes require flour, sugar and active dry yeast.
Betty Crocker recommends making a simple starter at least one week ahead of time. Mix 1 1/2 teaspoons of quick active yeast with 4 cups of warm water, and stir until the yeast dissolves. Fold in 3 cups of flour and 4 teaspoons of sugar, and beat the mixture on medium speed for about a minute. Loosely cover the starter, and allow it to stand for about a week at room temperature. Cover tightly and refrigerate once the mixture is bubbly and smells sour. Already-made sourdough starters are available through most grocery retailers.
To make Betty Crocker's crusty 1 1/2-pound sourdough loaf, add 1 cup of starter, 3 cups of bread flour, 2 tablespoons of sugar, 1 1/2 teaspoons of salt and 1 teaspoon of quick active dry yeast, along with 1/2 cup of water to the bread pan in the order recommended by the manufacturer. Bake using a basic, white bread cycle with a light or medium crust.
A 2-pound sourdough loaf without a starter requires 1/2 cup of sour cream, 2 tablespoons of white vinegar and 2 tablespoons of salted butter in addition to 4 cups of bread flour, 1 tablespoon of sugar, 1 teaspoon of salt, 1 3/4 teaspoons of yeast, and 1 cup plus 2 tablespoons of water. Add the ingredients to the bread machine in the order suggested by the manufacturer, and bake on a French bread cycle with settings for a medium crust.