For the pasta omelet, boil plenty of salted water in a saucepan. Cook the spaghetti in it for 8 to 10 minutes until al dente.
Wash bell bell pepper and cut into small pieces. Clean mushrooms and cut into thin slices.
Heat one third of the oil in a saucepan. Brown the chopped onion, garlic and mushrooms. Add peppers and peas and cook. Add tomatoes. Bring to a boil and season with salt, pepper and dried oregano. Cover the lid and simmer on medium heat for about 10 minutes.
In the meantime, pour the spaghetti into a sieve and let it drain. Mix eggs and season with pepper and salt. Stir in cheese and mix with drained spaghetti and eggs.
Heat remaining oil in a large frying pan until hot. Fry a pasta omelet with the spaghetti and egg mixture and serve with the fried tomato vegetables.