750 ml water
3 egg
3 grams sea salt
250 grams buckwheat flour (farine noir)
50 grams all purpose flour
50 grams melted butter or olive oil
Whisk 250 ml of the water with egg and salt to combine.
In a separate bowl, mix both flours together. Make a well in the centre. Gradually whisk in water mixture. When you have a smooth paste, whisk in remaining water to make a thin batter. (The consistency similar to 35% cream.) You may not use all 500 ml . Set aside at room temperature for 2 hours.
Stir melted butter or oil into batter when ready to cook galettes.
Filling.
Make a bechamel sauce and add the ingredients you want, bacon, boiled potatoes, sausage, or vegetables. Try a full English breakfast on/in a galette, or a Toulouse sausage with ketchup wrapped as Breton hot-dog.