Measure 360g warm water, sugar, olive oil, and bread flour into a medium bowl. Stir with a sturdy metal spoon until combined, then finish mixing with a wet hand. Cover and rest for 30 minutes. This is your autolyse — it lets the flour fully hydrate before adding salt and yeast.

After 30 minutes, combine 20g warm water, yeast, and salt in a small container and mix to combine.

Once you have a yeast-salt slurry, add to the dough then wet your hand and use it to mix the dough until the salt and yeast are relatively well combined with the hydrated flour. This should take about 60 seconds. My preferred move for combining things here is to use a claw like squeeze. At this point the dough will be super shaggy and sloppy and that's totally ok as long as there are no large clumps. If there are, continue working those out by hand.

Cover and ferment at room temperature for 30 minutes.

30 minutes later, Perform a strength-building fold. To do that, grab a section on one side of the dough and stretch it up until you meet resistance. Fold that stretched portion of dough across to the other side of the bowl.

Repeat this fold 4-5 more times around the bowl until you have a dough ball that’s tucked into a little package. Flip the dough over onto the folded seams and round off the dough ball by tucking the dough under itself as you rotate it from 10 o'clock to 2 o'clock to create surface tension. Watch my recipe video for a live demonstration of how I do this.

Cover the bowl and rest 30 more minutes.

30 Minutes later (or 60 Minutes after finishing the mix), complete a second strength-building fold. Same as before: grab a section on the side of the dough, stretch it up, fold over to the other side, rotate the bowl and repeat 4-5 times. You’ll then round the dough again using a 10 to 2 o'clock tucking motion to create surface tension until the dough is a nice, tight ball.

Cover the bowl and transfer to the fridge for 4-24 hours.

Pour about ¼ cup olive oil into a 12-inch cast iron skillet and then transfer the cold dough into the oiled pan. When placing the dough in the pan, the bottom side that was touching the bowl should now be facing up in the cast iron pan.

Using oiled fingertips, dimple and gently stretch the dough out toward the edges of the pan. Don't force it. If it springs back, let it relax for a few minutes and try again. Cover and place in a warm spot (ideally above 70F/21C) to proof for roughly 60 minutes. If your house is cold, preheat your oven to 500F/260C early and put the cast iron on the stovetop to enjoy the toasty micro climate around the oven.

60 minutes later, drizzle the top of the dough with a touch more olive oil, then dimple the dough again with your fingertips 10-12 times, pressing all the way to the bottom of the pan.

Cover and let proof for about 30 more minutes or until the dough has doubled from its original size and looks jiggly, buoyant, and is full of air bubbles.

Preheat your oven to 500F/260C if you haven't already.

Sprinkle the top of the dough liberally with flaky salt.

Bake for 15-18 minutes until the top is deeply golden brown on top and fully risen. Bake it darker than you think. One of the main benefits of the longer overnight fermentation is the deep complexity of flavor you get from browning the crust hard. Same day short ferments lack this depth.

Immediately remove the focaccia from the pan and place on a cooling rack. Let it rest for at least 15-20 minutes before cutting. (If you cut in too early, steam escapes and the inside could be gummy)