Dissolve the yeast in the buttermilk and rub the saffron threads with the salt.
Work the flour, saffron, yeast, coriander and butter into a dough.
Knead the dough with your hands on a floured work surface to form a smooth, elastic dough.
Cover the dough and let rise in a warm place for about 1 hour.
Divide the dough into 2 parts and roll into thin strands about 60 cm long. Twist these in a spiral shape and place on 2 baking trays lined with baking paper. Cover the rolls and let rise in a warm place for another 45 minutes. The volume should double.
Preheat the oven to 250 ° C.
Brush the snails with water and sprinkle one dough snail with sesame seeds and the other with sunflower seeds.
Put the snails into the oven on the second rail from the bottom, lower the temperature to 200 ° C and bake for 30 minutes.