Combine sausage, beef and red pepper flakes in a skillet over medium heat; cook and stir until meat is brown and crumbled, 7 to 10 minutes. Drain excess fat; place in a bowl.
Cook onion, bacon, and garlic in the same skillet over medium-low heat until bacon is crisp and onions are soft, 10 to 15 minutes.
Combine water and chicken broth in a large pot; bring to a boil. Stir in potatoes; cook and stir until soft, about 15 minutes. Pour in cream; simmer until heated through, about 2 minutes. Add sausage, onion mixture, and spinach; cook and stir until flavors combine, about 20 minutes. Serve with polenta or cornbread.