I don't know how authentic the crepe recipe is but the consistency works really well. The key is to make sure there are no lumps so the crepes spread evenly when cooking. Buckwheat is a delicious nutty grain so go with it!
Of course you can remove the salmon if you want to make it vegetarian. And if you have eagle eyes, you'll notice some green in the picture. There was some extra sautéed swiss chard so I added it. But it isn't necessary and I didn't want to over-complicate the recipe.