Cream of Sausage-Sauerkraut Soup

When you make bratwurst cooked with sauerkraut,
and serve it with baked or roasted potatoes,
the leftovers are the perfect beginning to soup the next day.

Heat butter in a pan.
Saute onions in it, if you want to.
Add chopped kale or spinach if you have it.
I made it today without either onions, kale, or spinach,
but they really do improve it.
When they are softened,
add chopped sausage (Polish works fine, too),
and all the sauerkraut,
and cook a little before adding a couple of tablespoons of flour.
Stir well, and add a little chicken broth and your chopped leftover potatoes.
Heat to very hot,
then temper cream or milk with it before adding all of it back to your pan.
Stirring often, cook until thick and bubbly.
Even my soup-hater asks for seconds.