This is the first time I’ve seen such significant growth both during the bulk fermentation and the oven spring. I followed u/Meliacet’s recipe but made a few tweaks to the flour composition and protein content.
Ingredients & Stats
250g Tipo 00 flour
230g German Type 550 (All-purpose)
20g Vital Wheat Gluten (to boost strength, as it's 80% protein)
Water: 345g (73% total hydration including starter)
Starter: 140g
Salt: 12g
Process
Autolyse: Mixed flour and water, rested for 1 hour.
Mix: Incorporated 140g starter and 12g salt. Rested for 30 mins.
Strength Building: 4 sets of stretch and folds every 30 mins.
Bulk Fermentation: 5 hours at approx. 21°C (70°F) room temperature.
Cold Proof: 5 hours in the fridge.
Bake: Preheated Dutch oven at 250°C (480°F).
Baked for 25 mins with the lid on (added ice cubes for steam).
Finished for 15 mins at 200°C (390°F) with the lid off.
The addition of the Vital Wheat Gluten really seemed to help with the structure since I didn't have any high-protein bread flour on hand. Very happy with the result!