Cook Italian sausage and red pepper in a frying pan over medium-high heat until crumbly, browned, and no longer pink, 10 to 15 minutes. Leaving some drippings.
Cook onions and garlic in the same pan over medium heat until onions are soft and translucent, about 5 minutes.
Move the onion mixture to a large pot. Stir in chicken broth and bring to a boil over high heat. Add potatoes and simmer until fork tender, about 20 minutes.
Reduce heat to medium; stir in cream, cooked sausage, and spinach. Cook and stir until spinach has wilted and sausage is warmed through
Serve and top with cheese.