In a large pot over medium-high heat, brown the Italian sausage for about 5-6 minutes, stirring often until fully cooked and no longer pink. Remove the sausage from the pot.

Lower the heat to medium, add unsalted butter to the remaining drippings, and let it melt. Stir in the diced onion and cook for 3-4 minutes until translucent.

Add minced garlic to the pot and sauté for about 1 minute until aromatic.

Pour in chicken broth and water, followed by sliced potatoes, salt, black pepper, and red pepper flakes. Bring to a boil.

Reduce to a gentle simmer, cover, and cook for 12-15 minutes until the potatoes are fork-tender.

Stir in chopped kale and cook for an additional 2-3 minutes until just wilted.

Lower the heat and slowly pour in heavy cream, stirring gently. Do not let it boil.

Add the cooked sausage back into the pot, stir to combine, and adjust seasoning as necessary.

Ladle the soup into bowls and garnish with crispy bacon and parmesan cheese.