Step 1

Combine the all-purpose flour, bread flour, sugar, yeast and salt in the bowl of a stand mixer fitted with the dough hook attachment. Add the water to the center of the bowl and mix on low speed to combine. Raise the speed to medium and knead until the dough pulls away from the bowl in a smooth, clean mass, about 10 minutes.

Step 2

​Lightly flour your workspace, turn the dough out of the bowl and lightly knead for about a minute, then shape into a ball. Lightly oil the inside of a large bowl, add the dough and rub oil over the top. Cover the bowl tightly with plastic wrap, then put in a warm spot, such as the top of the fridge, until it’s more than doubled in size, about 45 minutes.

Step 3

​When the dough is almost ready, preheat the oven to 450 degrees F with a rack in the middle position. Stack two matching baking sheets and place in the oven. Or, if you have a baking stone, use that instead.

Step 4

Turn the dough out of the bowl, punch it down and flatten it until it’s about 2 1/2 inches thick. Shape the dough into a boule (round loaf). Lightly flour the top, cover lightly with plastic wrap and let rise for another 25 minutes.

Step 5

​Remove the plastic wrap and score the top of the loaf. Open the oven door all the way and use a baking peel or the floured underside of a baking sheet to slide the loaf onto the hot stacked baking sheets or baking stone, working gently but quickly so as not to deflate the dough. Bake for about 10 minutes, then open the oven door and carefully throw a few handfuls of water at the bottom of the oven to create steam. Close the door quickly and continue to bake until well browned, 12 to 15 minutes more.

Step 6

Reduce the heat to 325 degrees F and bake until the loaf is deep golden brown and sounds hollow when you tap it, 15 to 20 minutes more. Transfer the loaf to a wire rack and let cool completely, at least 1 hour. That lets the crumb set. Listen to the loaf crackle as it cools—that’s a good sound. Serve at room temperature.