Pour hot water over the flakes and let them swell.
Mix the flour, sunflower seeds and 300 g lukewarm water in the food processor, leave to stand for 20 minutes.
Then add the swollen flakes, salt and sourdough and knead well. If necessary, add a little more water.
Let the dough rest for about 2 hours.
Then place on the lightly floured work surface, cut in half and form into two loaves. Let them rise in the proofing basket for another 2 to 3 hours.
Preheat the oven to 250 ° in good time.
Turn the bread out of the basket and cut into it several times, put it in the oven, spray water into the oven. After 10 minutes of baking, reduce the temperature to 220 ° and bake for another 40-50 minutes.