Place a Dutch oven or large soup pot over medium heat and add the ground turkey sausage.
Sauté the sausage, breaking it apart with a spoon until browned and fully cooked, about 5 to 6 minutes.
Remove the sausage from the pot and set aside, leaving the rendered fat if desired or draining if preferred.
Add the butter to the pot and stir in the onion, sautéing until translucent.
Add the garlic and cook until fragrant.
Pour in the chicken broth and water, then add the potatoes.
Bring the liquid to a light boil, then reduce heat and simmer until potatoes are tender, about 15 minutes.
Stir in the heavy cream and the cooked sausage.
Add the chopped kale and cook for another 3 to 5 minutes until the kale is wilted and tender.
Season with salt and pepper to taste and serve warm with optional toppings.