Spain (Catalonia) · hearth

Pan de Cristal

Target 95% hydration · sheet pan · bake at 500°F

Pan de Cristal ('glass bread') is the Spanish extreme-hydration hearth bread. 95%+ hydration produces a crumb so open it's nearly hollow — hence 'glass.' The dough includes 5% olive oil, which lubricates the extreme hydration and allows handling. Very difficult for beginners; requires wet-hand and bench-scraper technique throughout.

Hydration
95%
Salt
2.00%
Levain
10–15%
Bulk @ 76°F
4.00h
Proof @ 76°F
1.00h
Bake temp
500°F
Bake time
20m
Vessel
sheet pan

Flour mix

Technique

Mix in stand mixer: all flour, 60% of water, oil, salt, levain. Gradually add remaining water over 5-10 min while mixing until dough is fully developed but extremely loose. 4 sets of coil folds every 30 min in first 2h, then rest for 2 more hours. Gently tip onto heavily oiled sheet pan. Cut into 4-6 rectangles with oiled bench scraper. Short 1h proof. Bake 500°F with steam, 18-22 min.

Calculator pre-set to Pan de Cristal's target (95%)

Adjust the slider for personal preference within the workable 90105% range.

Flour to add
450 g
Water to add
425 g
Salt
10 g
Levain @ 100%
100 g
Total dough
985 g
Effective hydration
95%
How the math works

Total water = flour × hydration %. Your levain contributes 50 g flour + 50 g water — both count toward the totals. You add only the remainder as fresh flour and water.

Salt % is computed on total flour weight, not final-dough flour.

Open 95% hydration guide →