Add flour, yeast, salt, coriander seeds and sunflower seeds in a big mixing bowl. Stir and add Water. Knead with the kneading. Let it chill for 60 minutes. Knead again and put into a baking pan chill for 30 minutes.
Preheat the oven to 250 degrees.
Slide on the lowest track and pour a dash of cold water onto the oven floor; Quickly close the door, the vapor does not escape.
Bake for 10 minutes and then reduce to 200 degrees and bake for another 30 minutes.