Whisk to combine buckwheat flour, ground flaxseeds, onion powder, garlic powder, and salt in a large bowl. Add the water, then whisk the ingredients to make a smooth batter.
Heat a medium-sized nonstick skillet or pan over medium-high heat. Brush the pan with some oil.
In a spoon or ladle, take a small amount of the crepe batter. Add the batter, and tilt the pan or spread the batter with a silicone spoon to coat the base of the pan. Cook until the edges of the crepe are crispy.
When you see the edges are turning into brown color, usually after about 45 seconds, flip the crepe carefully with a flexible silicone spatula. Cook the other side of the crepe for about 15 to 20 seconds.
Take out the finished buckwheat crepe and place on a plate. Repeat this process until all the batter is used.
Serve the buckwheat crepes immediately with your favorite toppings and fillings.