Brown sausage in a large pot for 5–6 minutes. Remove and set aside.
Add butter and onions; cook until translucent. Add garlic and cook 1 minute.
Add broth, water, potatoes, salt, and pepper. Boil until potatoes are tender.
Stir in kale and heavy cream.
Return sausage to pot and simmer briefly.
Top with parmesan or bacon if desired.
