Hi Lisa! Adding ice cubes or water in your oven can really assist with crust progress (especially when baking sourdoughs!). While It's not necessarily Totally essential, it might help develop a good looking loaf. Here is a little bit additional information on the process: Baking bread with steam Delighted Baking! https://bydauto336802.blogerus.com/50912566/detailed-notes-on-sourdough-traduction