In a large mixing bowl, combine the all-purpose flour, salt, and instant yeast. Whisk them together until well mixed.

Pour in the water and stir with a wooden spoon or spatula until a shaggy dough forms. Don’t worry about mixing it too well; it’s supposed to be sticky!

Cover the bowl with plastic wrap or a damp kitchen towel. Let it sit at room temperature for 12 to 18 hours, or until the surface is bubbly and the dough has doubled in size.

Lightly flour a countertop and gently turn the dough out onto it. Handle it with care, as you want to keep as many air bubbles as possible. Cut it into two pieces using a bench scraper.

Shape each piece into a rough rectangle, then place them on a floured parchment paper. Cover with a kitchen towel and let them rise for another 1-2 hours.

About 30 minutes before baking, place a baking stone or an inverted baking sheet in the oven and preheat it to 450°F (232°C).

Carefully transfer the ciabatta onto the hot baking surface. Bake for 20-25 minutes, or until golden brown. The crust should be hard and the inside soft and airy.

Remove the loaves from the oven and let them cool on a wire rack before slicing.