Mix together in a large bowl:
450 gm bread flour (I use about 370 white and 80 wheat)
9-10 gm salt
¼ slightly rounded teaspoon dry yeast
Add:
350 ml beer (one can)
Stir the beer into the dry ingredients and form into a sticky ball of dough.
Put a plate or something on top of the bowl, and set aside (in a warm room, if possible) for 18-24 hours. If you want to leave it for longer, put it in the fridge for a little while to slow down the rising.
Sprinkle some flour on a clean surface (that you can later pick up — I use a plastic placemat) and use a floured spatula to loosen and pour the dough out onto the floured surface. As if it's a square, pull one side up and over, then another side up and over, then another, then another. Finally, pick up the gooey mass and turn it over. Put a big bowl over it (or a cloth, if you prefer), and let it rise for 2 hours. In cool weather, put it in the oven, set the temperature to 40ºC (104ºF)—my oven has a setting for rising 発酵—and let it rise for 2 hours. Remove dough from the oven.
Place a dutch oven, donabe, or other oven-safe covered pot into the oven and preheat to 230ºC (450ºF). Carefully remove the pot from the oven, sprinkle a little flour inside the pot to prevent the dough from sticking, and gently turn the dough into the pot.
Cover and bake for 32 minutes, then carefully remove the lid, and bake for another 20 minutes. Remove from oven. Check doneness with a thermometer. The bread should have an internal temperature of at least 96ºC (205ºF).
Cool on a rack before cutting.
