2 cups warm water
2 cups flour
3 TBS sugar
1 TBS yeast
1/2 tsp salt if desired
Mix all in a large bowl or container. Cover, but leave loose for escaping gas. Leave at room temperature for two days, stirring with a non-metal utensil when you think about it.
Make it at least a six cup container, I made this in a glass quart jar once and it oozed out all over my pantry. Cleaning that up wasn't fun! You can see my container here is way large. If I decide I like sourdough again I'll probably be on the look out for a smaller container. However, a plastic container with a cover like this is a great option as you can just shake the jar instead of stirring it. Just tighten the top and shake then loosen the top when you are ready to leave it again.
*after one day. Very nice and bubbly