Less of a recipe and more of a description. I made this up myself, such as it is.
In large pan over medium heat, combine 1 onion (finely sliced), 1 pepper (finely sliced), and 1 lb pre-cooked Italian-style Sausage (sliced). Saute for 10 minutes or so, until the veggies are all soft and melty and the sausage has been heated through and maybe browned a little. Meanwhile, cook up a pot of pasta (I like penne for this, but any sturdy shape will do). When everything's done, toss to combine and serve with parmesan cheese to top.