Good oven spring is one of the fundamental aspects of a great sourdough bread. Bakers are always looking for ways to improve the spring since it helps create that nice open crumb.
I have been baking bread for years following the pretty typical process of preheating the oven and dutch over for about an hour at 500 degrees. Steaming the oven and adding baking the bread for 20 mins covered then lowering the oven temp to about 450-475 and baking uncovered to get the right color. It generally works well.
I was reading about trying to turn off the oven in the first 20 mins to improve the oven spring and so I thought i would try it. I followed my normal process but when i put the dutch oven into the oven i turned off the oven and set a time for 20 mins. I was shocked at how nice it rose and even gave me a nice mini ear. I am not sure on the exact science but my guess is that the lower level of direct heat slows the evaporation of steam helping keep the moisture longer allowing the dough to stretch more gently.
Anyway, its worth trying, otherwise i used the Perfect Loafs recipe which is one of my personal favorites.
https://www.theperfectloaf.com/best-sourdough-recipe/
