Galettes de sarrasin, also known as galettes de blé noir, are savory crêpes made from buckwheat flour. They're also called crêpes bretonnes (Breton-style) as the dish originated in Brittany, France. The lacy crêpes are made in a very similar manner to sweet crêpes, but the difference is that buckwheat crêpes are cooked only one one side.
Originally, the "true" galettes were supposed to be served plain with salted butter, but these days, they're usually garnished with charcuterie meat, smoked fish, cheese or vegetables. The most popular version is called La complète which is composed of ham, emmenthal cheese and a cracked egg cooked directly on top of the galette. Another common one, La soubise, is filled with caramelized onions and salted butter. I filled mine with sautéed button mushrooms, red bell peppers and raclette cheese.
If you're only familiar with sweet crêpes, it's definitely worth giving these buckwheat crêpes a try. C'est absolument délicieux!