- 4 cups (20 oz) all-purpose flour or bread flour
- 2 teaspoons (10 g) kosher salt
- 1 teaspoon (4 g) instant yeast
- 2 cups (16 oz) lukewarm water
- olive oil
- flaky sea salt, such as Maldon
- 1 to 2 teaspoons whole fresh rosemary leaves, optional
- In a large bowl or mixer, mix together the flour, salt, and instant yeast.
- Add water and mix until the ingredients come together. Rest for 10-15 minutes and then mix for another 5 minutes.
- Oil the dough or plastic bag and place in refrigerator for at least 12 hours or for as long as three days.
- Line a half sheet pan with parchment paper and pour a tablespoon or two of oil into the center of the pan.
- Place the dough into the oiled pan. Stretch to mostly fill the pan, coat with olive oil and let rest for 3 to 4 hours or cover and return to the refrigerator over night.
- Set a rack in the middle of the oven and preheat it to 425°F. If using rosemary, sprinkle it over the dough. Using your fingers, dimple the dough all over. If necessary, gently stretch the dough as you dimple to allow the dough to fill the pan. Sprinkle with flaky sea salt all over.
- Transfer the pan to the oven and bake for 25 to 30 minutes, until the underside is golden and crisp. Remove from the oven and transfer the focaccia to a cooling rack. Let cool for 10 minutes and remove from pan.