Cook the Bacon
In a large pot or Dutch oven over medium heat, cook the chopped bacon until crispy. Remove with a slotted spoon and set aside, leaving the bacon grease in the pot.
Brown the Sausage
Add the Italian sausage to the pot and cook until browned, breaking it into small crumbles with a wooden spoon. Remove the sausage and set aside with the bacon.
Sauté Onion and Garlic
Add the diced onion to the pot and sauté in the rendered fat until softened, about 3-4 minutes. Add the minced garlic and cook for an additional minute until fragrant.
Simmer the Potatoes
Pour in the chicken broth and water. Bring to a boil, then add the sliced potatoes. Reduce the heat to a simmer and cook until the potatoes are tender, about 10-15 minutes.
Add Kale and Cream
Stir in the chopped kale and cooked sausage. Simmer for 5 minutes until the kale wilts. Reduce the heat to low and stir in the heavy cream.
Season and Serve
Season the soup with salt, pepper, and crushed red pepper flakes to taste. Garnish with the crispy bacon and serve hot with crusty bread.