The next day or next morning, preheat the oven to 450 degrees with your dutch oven placed inside while preheating - turn on your timer for 45 minutes.
Step 7: Preheat. The next day or next morning, preheat the oven to 450 degrees with your dutch oven placed inside while preheating - turn on your timer for 45 minutes. After turning on your oven, remove your sourdough from the fridge.