4 cups
all-purpose flour, plus more for kneading
2 teaspoons
kosher salt
8 tablespoons
extra-virgin olive oil, plus more for greasing
Flaky salt
Method
In a small bowl, sprinkle the yeast over the warm water. Whisk briefly, then set aside to proof for 5 to 10 minutes.
In a large bowl, whisk together the flour and salt. Pour in the bubbly water and, using your hands, mix until a shaggy dough forms. Set aside for 10 minutes.
Grease a second large bowl with 3 tablespoons of olive oil. Turn the dough out onto a floured surface and knead with floured hands until smooth, about 10 minutes. Form into a ball, place it in the oiled bowl, cover with a kitchen towel, and set aside until it has doubled in size, about 2 hours.
Preheat the oven to 450°F with a rack in the center position.
Grease a 9 x 13-inch baking dish with 3 tablespoons of olive oil. Transfer the dough to the prepared pan. Using oiled fingertips, press firmly into the dough and stretch it to the corners, making dimples as you go. Let rise, uncovered, in a warm spot for 30 to 60 more minutes.
Carefully drizzle the focaccia with the remaining 2 tablespoons olive oil and sprinkle it all over with flaky salt. Bake until puffed and lightly golden brown all over, about 25 to 30 minutes.