I recently bought a couple of brotforms from Luckyclover. I have baked my sourdough in it a few times, but so far I have not been able to retain the shape of my boule or the loaf! I love to see the marks on my loaf, even though it kind of slides on the side, but I wish I could have the right shapes. I tried making it with less hydration this time and still the same result. I must mention that I cover the inside with rice and all purpose flour. Before, I used a plain glass bowl that I covered in similar way and the boules always came out just fine.
Any advice/tips will be appreciated.