Brown the Sausage: Cook the Italian sausage in a skillet over medium heat until browned, then drain the excess fat. For the Kielbasa Option, lightly brown the kielbasa slices in the same skillet; you can use them instead of the Italian sausage or combine both.
1 pound ground Italian sausage, optional: 12 ounces kielbasa
Load the Slow Cooker: Transfer the sausage and optional kielbasa to the slow cooker. Add the garlic, onion, potatoes, salt, pepper, and chicken broth.
1 tablespoon minced garlic, ½ medium onion, 4 medium russet potatoes, 1 teaspoon salt, 1 teaspoon black pepper, 4 cups chicken broth
Stir Everything: Mix to evenly distribute the ingredients.
Cook the Soup: Cover and cook on low for 5–6 hours or on high for 3 hours, until the potatoes are tender.
Add the Cream: Pour in the heavy whipping cream, cover again, and cook on low for 10–15 minutes until warmed through.
1 cup heavy whipping cream
Finish and Serve: Ladle into bowls and top with Parmesan cheese.
¼ cup grated Parmesan cheese for serving