Crumble the sausage onto a baking sheet. Bake the sausage until it is no longer pink, about 30 minutes.
Drain the fat and grease off the bacon using paper towels.
Prepare the bacon. You can either pan fry or bake the bacon, according to your own preference. Crumble bacon into small pieces.
Cut the potatoes into bite sized pieces, about ⅛ inch to ¼ inch, making the pieces all about the same size so they cook evenly.
Using a large pot, toss the potatoes, onion, garlic, chicken broth, and water in together and cook on medium heat until the potatoes are cooked through.
Add the sausage, bacon, red pepper flakes, and salt and pepper to taste. Simmer, stirring occasionally, for another 10 minutes.
When the potatoes start breaking apart because they are so tender, turn the heat to low and stir in the kale and heavy cream.
Let the soup heat through and serve.
Notes
To make this recipe in the slow cooker, just prep everything through step 5 in the recipe card below. Then dump all the remaining ingredients in the slow cooker and cook on high for 4 hours or low for 6 hours.