Two months ago I bought a new oven so I had to learn how it works, I mean what is the best setup for sourdough heart baking. This led me to change my setup: no more covered baking!
Have you ever seen the incredible oven spring, great crust color, beautiful ears you have with a professional steam injected deck oven? Just take a look at these photos from Wally's excellent post "My Excellent Adventures at King Arthur Flour".
[James scoring Pain au Levain]
[Jeffrey at the oven]
Don't you think this is incredible? How can this "flat dough" spring up so well? It must me the oven+steam system!
Here is one small (470g) test loaf, nothing special, just a white liquid sourdough and stone grounded Italian Tipo1 flour - very close to T80 French flour - a medium/soft+ dough at 66% hydration. I didn't take too much care of the dough because I was focused on my setup, but ...
So, the new setup is simple: free steam in the oven generated with a pre-heated bread loaf pan filled with stones and a wet towel. Preheat the oven at 250°C for about 45 minutes with the stone and the pan inserted (the pan is on the same level with the stone) and put the wet towel in the pan just before inserting the bread in the oven. My oven is very well insulated and it traps all the steam, moreover the top heating element work well and doesn't get fire-hot. When I baked this dough with the lid it was very flat with no ears ...
I think I have finally removed THE variable that gave me somewhat inconsistent baking result.