Potato Spinach Soup - cooking recipe

Ingredients

1/4 cup butter
1 large onion
2 stalks celery, cut fine
1/4 cup flour
3 cups water
2 cups potatoes, cubed
2 teaspoons salt
1 cup spinach, chopped (I use frozen)
1/2 cup cream (when dieting, I use canned evaporated skim milk)
to taste swiss cheese, shredded or to taste parmesan cheese, grated, shredded (optional)

Preparation

Melt butter in a pan.
Add onions and celery.
Cover and cook until tender - about 15 minutes.
Stir occasionally.
Blend in flour, and add potatoes, water and salt. Stir constantly until boiling.
Simmer 30 minutes.
Add spinach cook 2 minutes.
Then add cream.
Top with grated cheese if desired.