Bring large pot of salted water to a boil. Add pasta and cook until almost done; add peas and continue to boil, 1 to 2 minutes or until pasta is cooked through and peas are tender.
While this is going on, cook onions in olive oil until tender. Cut salami into thin slices and then julienne into 1/4 inch strips.
Drain pasta and peas and toss with onions, salami and tomatoes. Toss to combine well, season with salt and pepper and serve with lots of freshly grated Parmesan cheese.