Preheat the oven to 170F (optional, to keep the pancakes warm once you’ve made them).
In a large bowl, add the milk and eggs and whisk until smooth. Whisk in the flour and salt until thoroughly combined and no lumps remain. The batter should be runny - if it’s too thick, add a splash of milk (you’ll know for sure once you make your first pancake!).
In a large (10-12-inch) skillet over medium heat, add the butter. Once the butter has melted, pour it into the batter and stir to combine.
Pour a scant ⅓ cup of the batter into the skillet and immediately tilt and turn the skillet so the batter forms a uniform thin layer (amount of batter depends on skillet size, watch the video for a demo). If the batter is too thick/is not easily coating the pan as you tilt/turn it, then stir some more milk into the batter.
Cook for about 1-2 minutes or until golden, then flip and cook for just one more minute. Transfer to a baking sheet or oven-proof plate/dish, cover loosely with a kitchen towel or tin foil. Repeat with remaining batter, adding a bit of butter to coat the pan for each pancake.
Arrange your fillings on the table and assemble your crepes! Place the fillings in the center of the crepe and then use a fork to roll it up (see video).