In a bowl or measuring jug, whisk together the milk (and water if your recipe contains ), eggs and vanilla seeds to obtain a homogeneous liquid.
Melt the butter in a small saucepan.
Form a well in the middle of the flour, then gradually pour in half the liquid mixture, mixing constantly with a circular motion in the center with the whisk. The flour gradually collapses in the center.
Tap the sides of the bowl to help the flour fall into the middle, always working from the center outwards.
Once all the flour has been perfectly incorporated, you should obtain a smooth, homogeneous, lump-free batter as shown below.
Then, add the remaining milk and egg mixture and mix well.
Finally, add the warm, but not hot, melted butter and mix until well incorporated. You can flavour your batter to taste.
Your crepe batter is silky smooth and lump-free. If you still get lumps, which you won't if you follow the step-by-step instructions, give the batter a whirl with a mixer or pass it through a fine mesh strainer.
Cover the bowl and leave to stand for 30 min to 2 hours, depending on your recipe. I usually leave for 1 to 2 hours before cooking.
Once the resting time has elapsed, cook your crepes and serve them with the topping of your choice.