In a large bowl combine flour, sugar, eggs, and butter

Add 1/2 cup of milk at at time, stirring vigorously, making sure the batter is smooth before adding more milk

Strain the batter through a fine mesh sieve. The batter should be verry liquidy and have no lumps. Rest in fridge for at least 30 minutes.

In a nonstick pan over medium heat (4) (melt a slice of butter before each crepe) pour 1/2 cup batter in the center and swirl around to the edges of the pan

Cook the crepe for 3 minutes, then flip and cook 1 more minute. Transfer crepe to wire rack to cool. Repeat with remaining batter.