Pour the sourdough starter into your mixing bowl. The sourdough needs to be active and recently fed (4-6 hours ago). Add 2 cups of the water.
Add the salt and mix thoroughly.
Add all the flour and 2 more cups of water. Mix all ingredients with your dough whisk, wooden spoon or your hands.
When all ingredients are well incorporated, cover the bowl and set aside to rise at room temperature. (75 ℉ is ideal)
After about 4 hours, check your dough. It should be almost double. Don't wait for it to double or it might over-proof. It will continue to rise for a while longer in the fridge too before it cools down enough for this action to be retarded.
Place the dough into your refrigerator or root cellar for at least 24 hours. Several days is better and up to a week is fine.
Prepare your oven by placing aluminum foil at the bottom. This is optional but helps especially when you have strong bottom heat, to keep your bread from scorching. Turn your oven on and preheat to 450 ℉. If you have a cast metal Dutch oven, place it in the oven now to preheat that as well.
Place a piece of parchment on a cutting board or sheet. Take your sourdough out of the refrigerator and loosen the sides and bottom. Turn the dough out onto the parchment. Take it to the oven.
Take your baking vessel out of the hot oven and, with a pot holder, remove the hot lid. Place it on a fireproof surface. Grab all 4 corners of the parchment and lift the dough into the pot including the parchment. Straighten the sides a little and sprinkle a little water over the top. Replace the lid (use the potholder!)
Place the Dutch oven back into the hot oven and bake at 450℉ for about 15 minutes. Turn down the heat to 325℉. Continue baking for 1½ hours.
If you want to cook in the BBQ grill, I find that I need to turn the pot after the first hour, half way around to make sure it bakes evenly.
Check for doneness. Be careful to remove the lid away from you to stay clear from any escaping steam. Stick a knife into the middle and if it comes out clean, it'll be done. A thermometer works really well here, I highly recommend using one. Bake till the middle temperature reads 195 degrees.
When done, turn off the heat and let the bread sit in the pot for about 10 more minutes. Then take the pot out of the oven and, using a potholder, remove the lid. Grab the ends of the parchment and carefully lift the hot bread out of the Dutch oven and onto a cooling rack.
At this point, you should let the bread cool completely before cutting it, and preferably overnight. Wrap it in a clean tea towel or flour sack towel. If you prefer a soft crust, use a wet towel to wrap it.
Slice the bread, but be careful, if you opted to make a hard crust bread. It's easy to slip and cut yourself. A long, serrated bread knife is recommended.
Enjoy your awesome ancient grain sourdough bread! Do try it toasted with some cheese and smoked ham or salami. Or with some raw nut butter. Check out how I use it to make my favorite breakfast. If you want a soft crust, you can check my complete instructions here .