In a large pot of boiling water, cook the fettuccini al dente according to package directions. Drain and set aside.
In a food processor, process together the avocado, cream, olive oil, and coriander into a smooth sauce. Season with salt and pepper and transfer to a large frying pan. Add the sweetcorn and pasta, and sauté over medium heat for 5 minutes or until heated through. Serve topped with the cheese and tomatoes.