Place water, milk, egg, egg yolk and salt into a blender or large mixing bowl. Blend or whisk together until eggs are completely incorporated. Add flour to liquid ingredients then mix until silky smooth. If you’re making sweet crepes, add the sugar and vanilla along with the flour.
Once batter ingredients have incorporated completely, add melted butter then mix well. If possible, let batter rest at least 30 minutes at room temperature, or cover and refrigerate up to 24 hours.
Prepare work area before you begin making the crepes by having a 10" non-stick skillet, rubber spatula, softened butter or cooking spray, paper towels, ¼-cup measuring cup, cooling rack and a clean kitchen towel at the ready.
Place skillet over medium to medium-low heat and let skillet warm to temperature. When the skillet is hot, add a small amount of butter or cooking spray to skillet then wipe with paper towel to create the thinnest coating possible.
Remove skillet from heat and hold it in your hand while you pour ¼ cup of batter directly into the center of the skillet. Tilt and swirl skillet to thoroughly coat the entire bottom, but not the sides with batter. Return the skillet to heat and let the first side cook for about 1½–2 minutes, or until the top has gone from a glossy liquid look to a pale matte look.
Use a rubber spatula to loosen edges of the crepe from sides of the pan, if they haven’t already pulled away on their own. Slide the spatula under the center of the crepe and flip. Cook on the second side for approximately 30 seconds then transfer to cooling rack.
Continue this process until all of the batter has been used up, wiping the skillet with a light coat of butter or oil before each crepe. Serve hot, or let crepes cool on the rack. Once they’re cool, they may be stacked on top of one another without sticking. Store the cooled crepes under the clean kitchen towel until ready to use or place in a gallon sized resealable plastic bag and refrigerate or freeze.
One Last Thing
Allowing your batter to rest will ensure light and delicate crepes!