Magic Onion Potato Soup

The magic is that you can make Magic Potato Soup
when your cupboards are nearly bare.
When anyone else would walk into your pantry
and declare that a meal could not be procured,
you can just grab a saucepan and smile.
In just moments (and with seemingly nothing at all),
you can produce a soup which is so flavorful
and lovely that your guests will beg for the recipe.
Upon receiving the recipe, they will insist that
you have left out an ingredient. Magic, I tell you.

Ingredients:
4-5 medium potatoes, peeled and diced
1 onion, sliced as thinly as possible
(the onion will “dissolve” and be absorbed
by the liquid almost completely by the time
the potatoes are cooked if sliced very, very thinly!)
1 teaspoon salt (and an optional dash of pepper)
3 1/2 cups water
1 tablespoon butter
1 tablespoon flour

Directions:
Combine potatoes, onions, water and salt
in a saucepan and cook until potatoes are tender.
Drain, reserving liquid. In the empty saucepan,
heat butter and flour until flour is browned.
Add the reserved liquid. Stir and cook until smooth
(use a whisk or fork).
Add potatoes and onion, then heat through.
Sprinkle with chives or parsley, if desired