Loaves of Pan de Cristal cut in half showing their very open crumb structure
Pan de Cristal

Pan de Cristal

Recipe by Martin Philip

Prepare yourself for a whole new kind of bread baking adventure. Pan de Cristal, otherwise known as Glass Bread, is a traditional loaf from the Catalan region of Spain. The high-hydration dough, which begins with a consistency so liquid it’s akin to pancake batter, stiffens up and becomes beautifully smooth and silky during fermentation. (The high protein content of our bread flour is a key ingredient for success here.) When shaped and baked, the result is a loaf with a shatteringly crispy crust and a beautiful, holey interior.  

Note: For help fitting this bread into your schedule, see the table in “tips,” below, for a hypothetical timeline.

Prep
40 mins
Bake
27 to 28 mins
Total
6 hrs
Yield
4 medium (5” x 7”) breads
Loaves of Pan de Cristal cut in half showing their very open crumb structure - select to zoom
Loaves of Pan de Cristal cut in half showing their very open crumb structure - select to zoom
Sliced Pan de Cristal loaves on a cheese board - select to zoom
Pan De Cristal - select to zoom
A few loaves of Pan de Cristal showing their open crumb - select to zoom
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Instructions

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  1. To make the dough: For best results, weigh your flour; this recipe was developed by metric weight. However, if you prefer to work with volume measurements, please be sure to measure your flour the King Arthur way: gently spoon the flour into a cup, then sweep off any excess.

  2. In a medium bowl, mix the water, flour, yeast, and salt until thoroughly combined and homogenous. Note: The dough starts off very slack and wet. That’s OK; it will transform itself through time and folds.

  3. Oil a two-quart rectangular baking dish (10" x 7") with the olive oil. If you don’t have a 2-quart dish, an 8" or 9" square pan will work. Don’t worry about any pan you use being oven-safe; you won’t be baking the bread in it.

  4. Pour the dough into the dish. Check the dough’s temperature by inserting a digital thermometer into the center. If it's less than 72°F, move the dish to a warmer spot, e.g., your oven with the light turned on.

  5. Cover the dish and allow the dough to rest for 20 minutes.

  6. Start with a bowl fold: Use your wet hands to grab a section of dough from one side, lift it up, then press it down into the middle. Repeat this eight to 12 times.

  7. Cover the dish and allow the dough to rest for 20 minutes.

  8. Then do a coil fold: With wet hands, reach under the dough and stretch the middle upward until the dough releases from the dish. Roll it forward off your hands, allowing it to fold over (or “coil”) on itself. This is called a coil fold. Rotate the dish 90° (a quarter turn) and repeat. Continue performing this folding action until the dough feels like it won’t stretch and elongate easily, usually four to five times initially. Note: You’ll be doing this three more times, each time building strength and developing the dough. See "tips," below, for more details,

  9. Cover the dish and allow the dough to rest for 20 minutes.

  10. Repeat the coil fold. Cover the dish and allow the dough to rest for 20 minutes.

  11. At this point, the dough should be easier to handle and feel tighter. Repeat the coil fold using only two or three folds this time. Cover the dish and allow the dough to rest for 20 minutes.

  12. Repeat the coil fold one last time, using only one or two folds if the dough is relatively strong. Cover the dish and allow the dough to rest for about 80 minutes.

  13. To divide the dough: As gently as possible, turn the dough out onto a heavily floured surface, maintaining the rectangle or square shape — be careful not to deflate the delicate dough. Sprinkle a generous amount of flour on top of the dough, leaving no exposed sticky spots. Then, working as gently as possible, use a bench knife or other sharp knife to divide it into four pieces. Gently place two pieces on a piece of parchment, leaving space between them. Repeat with the remaining two pieces of dough, placing them on another piece of parchment.

  14. Allow the loaves to rest at room temperature for 2 hours, uncovered. While the loaves are resting, preheat the oven to 475°F with a baking stone or steel on a lower rack. (If you don't have a stone or steel, see "tips," below.) Allow the oven to preheat for 1 hour to ensure it’s thoroughly heated. The loaves are ready for the oven when there are a few large bubbles on the surface of each loaf and they feel light and airy.

  15. To bake the bread: Carefully slide the two loaves (still resting on the parchment) into the oven onto the preheated stone or steel. If space is tight and the full sheet of parchment won’t fit on the stone or steel, cut the parchment between the two loaves and arrange them as best you can. Allow the other two loaves to continue to rest.

  16. Bake the loaves for 15 minutes, then transfer them, from the stone or steel, directly onto a rack in the upper third of the oven for an additional 13 to 15 minutes. (Leave the stone in place.) Moving them to the rack allows the baking stone or steel to become hot again in preparation for the next two loaves. After a total of 27 to 30 minutes of baking, remove the loaves from the oven and allow them to cool on a rack.

  17. Repeat the process with the two remaining loaves. Cool the bread fully before slicing.

  18. Storage information: Wrap the bread loosely and store it at room temperature for up to several days; freeze for longer storage.

Tips from our Bakers

  • In warmer months (or when your indoor temperature is 70°F to 75°F), the water used should be 80°F to 85°F. In cooler months (when your indoor temperature is around 65°F), use 100°F to 105°F water. The DDT (desired dough temperature) at the end of mixing is 74°F to 76°F.

  • Depending on the strength of your dough, you may not need to perform all four coil folds. If after the third coil fold, the dough feels relatively strong, tight, and is easy to handle, immediately allow the dough to rest for 80 minutes and skip the final coil fold. This will ensure an open crumb structure.

  • If you don't have a baking stone/steel: For best results, the dough should receive an immediate blast of heat as soon as it goes into the oven. A baking stone or steel is ideal for transferring heat, but if you don't have one, you can use a cast iron pan or another oven-safe skillet. Allow the pan(s) to preheat with the oven (step 14). A preheated baking sheet may also work, but results may vary and some baking sheets may warp in the oven when heated alone.

  • This bread stales (and its crust softens) quickly due to its high ratio of crust to crumb. Re-crisp the loaf before serving by heating it in a preheated 400°F oven, uncovered, for about 8 to 10 minutes.

  • Sample timeline:  
    12:00 p.m. Mix the dough
    12:20 p.m. Bowl fold
    12:40 p.m. Coil fold #1
    1:00 p.m. Coil fold #2
    1:20 p.m. Coil fold #3
    1:40 p.m. Coil fold #4
    3:00 p.m. Divide
    5:00 p.m. Bake

  • The maximum temperature rating for most parchment paper is below 500°F, and at temperatures between 450°F and 500°F parchment’s exposed edges begin to char. To be safe, keep a close eye on anything being cooked at temperatures above 450°F (especially anything on an upper rack). Burned edges can also be minimized by trimming away excess parchment before baking.

  • To make this dough into a bubbly focaccia: Drizzle 1 generous tablespoon (about 20g) of olive oil in the bottom of a 9" x 13" pan and spread to distribute. Instead of dividing the dough (step 13), use a slightly wet bowl scraper to gently ease the risen dough into the pan. Drizzle 1 tablespoon (15g) of olive oil over the top of the dough, then use your hands to very gently encourage it towards the corners. Cover the pan and let the dough rise for 2 hours, until it’s pillowy, with some large bubbles on the surface. In the last hour of the proof, preheat the oven to 475°F with a baking stone or steel on the lower rack. When ready to bake, drizzle the risen dough with a little more olive oil, then use wet or oiled fingers to make one pass of dimples all over the dough. Sprinkle with flaky salt. Bake for 25 to 30 minutes, until deeply brown and crisp. Immediately transfer the focaccia out of the pan onto a wire rack and let cool before slicing.