Blend at medium speed for 20 seconds, stop and scrape the sides of the blender jug with a spatula, and blend for 10 more seconds. Allow to mixture to rest for 20-30 minutes or overnight in the fridge.
Heat a 9-10 inch pan on medium high heat, and brush with a very small amount of butter, add ¼ cup of crepe batter to one side of the pan and very quickly swirl to coat the pan with batter. If there are any holes, add a little more batter to cover them.