Bring a large pot of salted water to a boil and add the pasta. Cook according to package instructions until al dente, usually about 10-12 minutes. Drain and set aside.
While the pasta is cooking, remove the sausage casings and crumble the sausage meat into a large frying pan. Cook over medium heat for 5-7 minutes until browned and cooked through.
Add the finely chopped onion and minced garlic to the pan with the sausages. Sauté for 3-4 minutes until the onion is translucent and fragrant.
Slice the red chilli and add it to the pan along with the halved cherry tomatoes. Cook for an additional 5 minutes until the tomatoes begin to soften and release their juices.
Stir in the fresh spinach and let it wilt for about 2 minutes. Combine the cooked pasta with the sausage mixture, tossing well to coat the pasta evenly with the sauce.
Season with salt and pepper to taste. Serve the pasta topped with grated parmesan cheese and enjoy immediately.