Take the spinach leaves, wash them and remove the thick stems

Place them in water and boil for about 8 minutes so that the spinach is well cooked
 
Wait for it to get Cooled and using a blender puree it , set aside after that
 
Take some butter and heat it in a pan
 
Now take the chopped onions and fry them over medium heat approximately 3 minutes till the onions are transparent
 
Plain flour must be added to the mix and fried over low heat
 
Combine the  milk, salt and pepper, spinach puree with it
 
Simmer over low heat for about 3 minutes.
 
Add the fresh cream before serving