In a large bowl, combine bread flour, salt, and instant yeast.
Pour in warm water and mix with a wooden spoon or spatula until a shaggy dough forms. The dough will be wetter and stickier than typical bread dough. This is exactly what you want for ciabatta.
Cover the bowl with plastic wrap or a clean kitchen towel and let the dough rise at room temperature for 2–3 hours.
During this time the dough will become bubbly, airy, and nearly double in size.
Lightly flour your work surface and gently turn the dough out onto it. Try not to deflate the air bubbles.
Using a bench scraper, divide the dough into two rectangular pieces.
Carefully transfer the pieces to a parchment-lined baking sheet.
Let them rest for another 30–45 minutes while the oven preheats.
Preheat your oven to 425°F.
For extra crust, place a small pan of hot water in the bottom of the oven to create steam while baking.
Bake the ciabatta loaves for 20–25 minutes until golden brown and crisp.
The crust should feel firm and the bread should sound hollow when tapped on the bottom.
Let the bread cool slightly before slicing.