I’m looking at the bottom crust and I’m not sure that you’re getting enough heat into the bottom. How low are you baking in your oven? Can you bake on a lower rack? Do you have a heat sink such as a baking stone or steel to bake on or are you using a dutch oven?
Either what Benito said (not enough heat at the bottom) or just a tad overproofing, which can cause collapse of the gluten network in lower part of the loaf
Comments
I’m looking at the bottom crust and I’m not sure that you’re getting enough heat into the bottom. How low are you baking in your oven? Can you bake on a lower rack? Do you have a heat sink such as a baking stone or steel to bake on or are you using a dutch oven?
Benny
Either what Benito said (not enough heat at the bottom) or just a tad overproofing, which can cause collapse of the gluten network in lower part of the loaf