Biga instead of sourdough instructions?

I have sourdough starter but I am unsure what is meant by 100% hydration. Does that mean ripe/unfed starter? Is a lesser hydration then one which has just been fed? Can’t wait to try this! Thanks so much for the recipe.

I don't have a suggestion for a biga, I'd have to test! Thanks for the link, Dr Babs 🙂

Here’s a recipe that uses a biga to make ciabatta. I think it’s similar to the one in The Bread Baker's Apprentice.
https://www.latimes.com/recipe/ciabatta