Mix 1 cup of wheat flour type 550 with 2 teaspoons of dry yeast and add 1 cup of lukewarm water. Mix everything well and close the bowl tightly with the corresponding lid. In the evening, stir 1 heaped tablespoon of flour type 550 into the dough.
Day 2:
Stir in 1 heaped tablespoon of flour type 550 in the morning and 2 heaped tablespoon of flour type 550 in the evening.
Day 3:
Stir in 1 heaped tablespoon of whole wheat flour in the morning and 1 heaped tablespoon of flour type 550 in the evening.
Day 4 and 5:
Stir the pre-dough only once a day and put it in the refrigerator on the evening of the 5th day, where it can stay on day 6.
Day 7:
In a large bowl, mix 3 cups type 550 flour, 1/2 cup whole wheat flour and 1 tablespoon dry yeast with salt and sugar. Add the pre-dough to the dry ingredients (please stir it beforehand!) And 1 cup of lukewarm water and knead everything well to form a smooth dough. Let rise in a warm place for 30 minutes.
Then briefly and only lightly shape on a floured work surface, place the loaf on a prepared sheet or put it in a mold. While the oven is heating up to 200 °, the bread can rise a little more.
The baking time of the bread is around 30 - 40 minutes. Then let the bread cool down covered on a kitchen rack.