Put chopped kale into a large stockpot and add enough water to cover the kale.
Bring to a boil over medium high heat; reduce heat and simmer about 30 minutes.
Remove from heat and set aside.
Put the cubed potatoes into a large pot and cover with water. Bring to a boil over medium high heat; add 1 tablespoon salt; reduce heat and simmer for 10-15 minutes or until tender.
Remove from heat and set aside.
Place the sausage in a frying pan over medium heat. Use the end of a flat spatula to break down the sausage into smaller pieces as it is browning. Remove from the pan and drain.
Add 1 tablespoon butter to the same frying pan and saute the onion and celery until tender.
Pour the cooked potatoes and liquid into the large stockpot with the cooked kale.
Add the drained sausage and cooked onion and celery to the same stockpot.
Add the 2 cups of milk and the can of evaporated milk and stir to blend.
Taste and add additional salt and pepper as desired.
Simmer uncovered for an additional 10 minutes or until ready to serve.
Notes
Garnish the bowls of soup with cooked, chopped bacon, if desired. The soup is just as good served as a left-over the next day.