In a large skillet over medium high heat, add a tablespoon olive oil and crumble and add the Italian sausage. With a spatula, crumble and brown the sausage into small crumbles until browned, about 5 minutes.
Add the onion, tomato paste, and garlic and stir until fragrant.
Put a large pot of salted water on to boil. Once boiling, add your pasta of choice and stir to ensure nothing sticks.
When the onion starts to soften, after a couple of minutes, add the chopped bell peppers. Stir the bell peppers for about 10 minutes, then add the tomato sauce and whole tomatoes (with all of the liquid in the can).
Using a spatula, crush the whole tomatoes while stirring everything together.
Cover with a lid, and cook until the peppers are soft. Depending how thin you sliced your peppers, that could be another 10-20 minutes.
During this time, your pasta will be done. Drain (but don’t rinse) the pasta and add to the pan with the rest of the ingredients.
The dish is done when the peppers are soft. Top with shredded cheese and spoon into large bowls.