Mix the levain ingredients together in a jar. Cover and set in a warm location (75-80ºF) for about five hours until doubled and bubbly.

When the levain is ready, mix the bread flour, warm water, salt, and levain into a medium-sized mixing bowl. Use a dough whisk to mix the very wet dough until all of the flour is hydrated.

Cover the bowl and transfer it to a warm location (75-80ºF) to proof in bulk fermentation for 4-5 hours. After 15 minutes, drizzle 1 TBS of olive oil on top of the dough. Perform a series of multiple stretch & folds* using wet hands. The first set will be extremely loose and sticky, which is normal. Rest for another 15 minutes and repeat.Rest for 30 minutes and perform a series of four coil folds in all directions. Repeat this twice more with a 30-minute rest in between. Rest for the remaider of bulk fermentation.At the end of bulk fermentation, the dough will at least double in size, be full of bubbles, and feel full of air.

Prepare a half-sheet pan with parchment paper and set it near your work surface.**Generously flour a work surface, hands, and bench scraper. Dump the dough out onto the work surface, gently pull into a square shape, and lift one side of the dough up and fold it to the center. Fold the opposite side up and over the other fold to create a rectangle letter package.Use the bench scraper to divide the dough into four equal-sized pieces and gently separate them with your hands. Transfer the breads to your prepared baking sheet with plenty of space in between each bread.

Proof the Pan de Cristal uncovered in a warm location for about 2 hours until they expand slightly and there are visible bubbles on the surfaces. To check if the breads are proofed, use a floured finger to poke the bread. The breads should leave a slight indentation that fills in back slowly. If the dough springs back immediately, proof them longer.

Preheat the oven to 500ºF (260ºC) for at least 30 minutes so the oven is fully preheated before baking.Once proofed, transfer the sheet pan to the oven and bake for 10 minutes at 500ºF. Then, lower the temperature to 425ºF (218ºC) and bake for another 20 minutes or until the crusts are dark brown.Cool for 30 minutes before slicing.