This may be my favorite hearth bread. When made well, it has an open crumb, which is unusual for 100% whole grain breads, and a deliciously sour and nutty flavor.
Whole wheat flour: 60%
Whole spelt flour: 30%
Whole rye flour: 10%
5% of the flour is in the starter, which could be whole wheat, whole rye or whole spelt, and can be 60% hydration or 100% hydration.
Whole wheat flour: 300 grams or 2 generous cups
Whole spelt flour: 150 grams or 1 generous cup
Whole rye flour: 50 grams or a generous 1/3 cup
Whole grain starter: 40 grams if stiff (a dough ball about the size of a golf ball); 50 grams if wet (about 3-4 Tbs)
Water: 375 grams or 1.5 cups + 1 Tbs
Salt: 10 grams or 1 and 3/8 tsp
Dissolve the starter into the water, and then add the salt. Mix the flours together well, and add to the water. Mix until everything is hydrated.
Dough development and the first rise
However you develop the dough, it’ll need to rise at room temperature for 8-10 hours. Use the wet finger test to see whether it’s fully risen in the morning.
Be gentle. You want to retain as many of those air bubbles as possible. Rounds and batards are the traditional shapes.
You can let it rise for another 2 to 3 hours at room temperature. You can also speed things up (and increase sourness) by placing the dough on an upturned bowl in the bottom of a picnic cooler, throwing a cup of boiling water in the bottom and covering it quickly. After an hour, throw another cup of hot water in. The rise should only take a couple of hours this way.
Score the bread as you like. Hash marks are traditional for rounds, and batards usually take a single, bold stroke down the center or a couple of baguette-style slashes.
While you can certainly bake this bread on a cookie sheet, it benefits from a stone and some steam, or a covered baker. However you do it, bake at 450 degrees for about 40 minutes.