Here is a really good sourdough bread recipe.

Bread Recipe:
4 cups white flour
1 cup whole wheat flour
1/8 cup flax flour
1/8 cup flax seed
1/8 cup sesame seed
1/8 cup chia seed
3 tablespoons honey or sugar
2 tablespoons olive oil
1.5 teaspoons salt
1 large tablespoon dried milk powder
1 pint hot water
1 cup crumbled pecans or walnuts
1 pint activated sourdough starter

Mix in a breadmaker and add more water if it is too thick. it should be a relatively wet bread mix but with lots of elasticity. Let the mix rise for an hour and punch it down. At 2 hours, punch down and separate into loaves on the baking pan, coat with oil or butter, put in the oven, and let rise another hour or so until the loaves have doubled in size. Bake at 375 for 26 minutes or until golden brown. Very few ovens regulate temperature properly so check the bread to get it right.

Care of sourdough starter: Store the starter in the fridge in a quart jar with a tight lid. To activate the starter, take the starter out of the fridge and add 1 cup flour and 1 cup water. Adjust the water until the mix is a bit thicker than buttermilk. Let sit on a plate at room temperature until the mix is bubbling freely, about 8 hours more or less. Be sure the lid is loose so pressure can escape. Room temperature or a bit higher is perfect for yeast to multiply. Lactobacillus likes 65 to 75, yeast likes 75 to 90 so I usually keep the house about 75 to get an optimum mix. Getting temperature right affects the flavor of the sourdough bread. Use starter per the recipe leaving about 2/3 of a cup in the quart jar. Place the jar back in the refrigerator. Be sure to use it again within 2 weeks to keep it active.

Add a tablespoon of honey or sugar to the starter to accelerate growth of yeast and reduce growth of the lactobacillus. This makes the bread less sour. Add a tablespoon of dried milk powder to the starter to accelerate the lactobacillus and reduce yeast growth. This increases the flavor.