Brown sausage
Add garlic and cook until fragrant
Add onion and bell pepper and sweat until the onions are translucent
Add the shells and toss to coat in the sausage fat. Then add in the chicken stock and marinara. Bring to a boil and reduce to a simmer. Simmer for 12-15 minutes or until the pasta is aldente.
Reduce the heat to low and add the heavy cream and the cheese. Stir under low (or off) heat until the cheese in incorporated.