Directions:
Take a tablespoonful of flour and three of water; make it boil and add the yolks of three eggs; melt one-half pound of butter and beat it gently into your first mixture, add salt, the juice of half a lemon and a pinch of grated nutmeg. Keep the sauce very hot in a _bain-marie_ or in a double saucepan. If you have neither, keep it in a large cup placed in a saucepan of hot water.