This is a 2 day recipe, start the night before

Mix ingredients for starter together, cover, and leave in fridge to chill overnight

Mix dough ingredients together, cover, and leave to chill in fridge for 2hr to overnight.

Next day, starter should show signs of fermentation, bubbly.

Put both starter and dough into any mixer, add in remaining yeast and salt. Add in ⅓ of the remaining water.

Mix everything at low speed until incorporated before mixing at medium high speed (I use 6) for few more minutes until all water is incorporated.

Repeat step 6 twice more until all 35g of water are used.

Add in olive oil and mix at low speed for 1 min before mixing at higher speed until dough comes together. Dough should not stick to the side of mixing bowl at the end. Dough should look smooth and the correct amount of gluten development will results in a very smooth and stretchy dough. Dough temperature should NOT exceed 25C or you risk having weak gluten. Ideal dough temp should be between 22-25C, lower is ok but make sure there is enough proofing time later.

Let dough rest until relaxed, do coil fold and let rest again, do total of 2-3 coil fold until dough retain its shape right after folding.

Let dough proof in the fridge (12hr) or in room temp (2-4hr) depending on schedule.

Properly proofed bread should have some resistance when pressing down and slowly return it's shape when dented.

Divide dough roughly into 4 portions, shape lightly with hand and dough scraper. Dust flour generously over the dough to make it easier to handle.

Transfer dough onto parchment paper or silpat.

Heats up oven to 450F, leave baking sheet in oven when starts. Add steam by adding bowl of boiling water in the oven when starting, this helps to create crispy crust.

Transfer the whole parchment paper or silpat onto baking sheet, bake for 15 mins or until golden brown.

Well baked ciabatta should have a crispy shell all around and hollow sounding when you tap the bottom.