Sourdough is amazing! If you have a small glass jar and a little bit of space, you can make have sourdough waiting for a list of baked goods. Purists may say that the addition of dry yeast is not correct, but truthfully, what difference does it make? If you think about it, your starter will constantly morph as you use it over time, and the wild yeast will eventually become the catalyst for the new starter. Adding yeast initially just gets everything off to a good start.
I keep my sourdough starter in a bean pot. It sits in my cupboard, instead of the refrigerator, but I use it every few days, so it stays active. You may want to keep your starter in the refrigerator until you want to use it, then just take it out of the fridge to warm to room temp, before using.
2 cups flour
2 cups warm water
1 package dry yeast (or 2 1/2 tsp bulk yeast)
Place all ingredients in a quart jar.
Stir until combined.
Cover, and store at room temperature for 2 days, or until pleasantly yeasty smelling.
Store in refrigerator if not used every week.
To use, remove what the recipe calls for, and replace with 1 cup each - water and flour. Stir and let stand until bubbly before placing back in refrigerator.