Cook spaghetti in a large pot of boiling salted water until al dente. Reserve 1 cup cooking water, then drain.
Add olive oil to a skillet and bring to medium-high heat. Add all ingredients and sauté for 2 minutes.
Add spaghetti to skillet and toss until combined well. (If pasta is dry, add some reserved cooking water.) If you do not want it to be vegan, sprinkle with parmesan cheese and fresh parsley. Otherwise, only sprinkle with fresh parsley to top.