For the creamed spinach, wash the fresh spinach and remove the stems. Scald briefly in hot water. Collect this water and use it for later infusion.
Rinse the spinach with cold water. Fry the onion in butter, dust with flour and pour the collected water.
Bring to a boil and add the spinach. Chop with a blender and bring to a boil. Add the cream and season with salt, pepper and nutmeg.